sneezing / personality change / bump

Question
My  male rat,Sammy, has been sneezing a lot for the past few weeks. I would like to get him to a vet but my mom thinks it will go away. He has also started to act a little different. His fur seems to always be sticking up like he is agressive and he will sometimes squeak when I lift him out of his cage. He also has a large benign tumor but is too old for surgery (2 1/2 years). I also found a tiny bump on his back that has been there for a while. It feels like a bug bite ang I don't know what it is. I wanted to take him to a vet and ask about it but my mom says that he just gets these problems because he is old so we don't need to do anything. Please tell me what these are and what to do. Thank you for answering.

Answer
Hi Maddi

He is NOT too old for treatment.  I have had rats live to be 3 and 4 years old. He is sick which is why his fur is puffed out.  

We need to find a vet for him so he can continue to live a happy life with you!
The smaller lump may be an abscess. Is there a scab on it?