What is wrong with my pet Rat??

Question
I have a 1.5 year old female rat that is very very sick.
I just want to know what is wrong with my pet rat. I have taken her to the vet twice already, but both were useless and not much help and both couldn't tell me what was wrong with her. The 1st vet put her on some antibiotics for a lung infection. But her lungs were not the issues as to why i brought her into the vet in the 1st place. All i said was she sneezes sometimes and he said that she has a lung infection. The second vet said to just continue with the antibiotics and she should get better with that. She hasn't and has gradually gotten worse over the past few weeks. No matter what we do. I did mention to both doctors about a Pituitary tumor but they both were dumb founded and didn't really know anything about it. These doctors were both exotic vets as well.
I do think she may Pituitary Tumor but now, as a bizarre symptoms appeared that i cannot find any info on so now im not to sure. The 1st onset of symptoms started about 2 weeks ago, with these symptoms:
1. Noticed that she had lost a lot of weight(this pet rat loved her food and she was a good chunky size. Not fat but chubby. And one day almost over night it seemed that she was so skinny and could feel her ribs.)
2. nipping at human hands. The nipping stopped once she was hand fed and full and will continue to nip at you if she is hungry.
3. Noticed she was unable to hold food and also noticed her finger and toe nails were longer and had been growing(my rats usually trim their own nails when cleaning themselves.) So this was odd as to why she was not grooming her nails as she usually does.  
4. Slow moving and getting tired easily. Had to take breaks during free play time
5. unexplained head movements in cage and in free play
6. porpythrin coming out of nose and eyes and caked on to the fore arms. She will also make herself more dirty as when she cleans herself porpythrin will come out of her nose. Have to cloth bath her.
7. Loss of balance. Having a very hard time cleaning herself and will fall over
8. Doesn't seem to be all there mentally. VERY TIRED
9. Will still want to come out for free play to walk around etc. But is very lethargic about it. And will need breaks
All these symptoms have been gradual and becoming worse as time goes on. She has lost the ability to use 1 arm as it is completely paralyzed. Her mental stability has dropped. She is kinda there in the morning. But once it goes into night it is like she is completely not there at all. and totally out of it.  So all the symptoms above have gotten progressively worse. Needs round the clock care and will not eat unless syringe feed. She loves her food. And will burx the whole time she is eating.
More symptoms started to development as time went on. For instance:
12. i have been checking on her pupils to see if one pupil is bigger than the other. During the 2 weeks pupils were fine and centered, expect for the last couple days. Since yesterday her pupils have been below her bottom eye lid. Perhaps she has become blind?? unsure.
11. Her vagina has become abnormal and started to swell with a reddish purple color. As if she was in abnormal heat or something. She still wants to explore. And my other rats will try and hump her. Which they only really do if that rat is in heat. It has gotten worse, and is now a greyish color and sometimes can be a hint of green. It is hard and im trying to cleaning it but its her skin that is that color. I am thinking that this has something to with a tumor. Or it is a very nasty infection that she has. Could what is happening to her not be a tumor at all and maybe just a major infection?
She still wants to eat. She is very into food, she isn't really into water at all. If i put it in her mouth she will just let it drop out of her month and wont swollen it. But she really likes her food still and will burxing just when food is in front of her. And she will eat alot about 3ml of baby food. She has gained weight and gaining more weight everyday. Please help just looking for answers

I have been watching her like a hawk and have been keep track of her symptoms. As i care deeply for all of my rats. <3
Shes already been to 2 different vets and no one could actually tell me what is wrong with her. I am going to take her to the vet again as the abnormality of her vagina was not present when i took her into the 1st 2 vets.
I know that a pituitary tumor can cause hormonal distributions. Would that be what is going on with her vagina? Something to do with a brain tumor? or could all of these symptoms be from a very nasty infection in hopes that we can save her.
i have posted about her before on here. I would just like some answer and wonder what you think she may have. And if i should be putting her down. As now she just seems like she is a vegetable.

Answer
I'm so sorry that your baby is very ill.  I've discussed this with another rat expert and we agree that it's possible it is a PT, especially since she is 18 months old...the time of menopause for most rats and when tumors often develop.  But the vaginal swelling and discoloring is a separate issue and may be a condition called pyometra.

I hate to delay advice but if you could get a short video of her movements, it would be a huge help in diagnosing her,  though I am not promising a diagnosis as I am not a vet.

If you could palpate her entire body and feel for any masses, that would be helpful.  Also, is one side of her face paralyzed or seem to be?  Sign of a possible stroke or severe ear infection.

 If you can't send a video through Allexperts, you can email it to me at irenemurphy@cox.net.  I look forward to hearing from you soon.