Unexplicable Puppy Pain

Question
I have a 5-1/2 month old Shih-a-poo, her name is Zoe and she is up to date on all of her shots, she is on Nutro puppy food and the only table food she has ever gotten is an occassional bit of scrambled egg.  She began whimpering and whining last Friday night, she had not been doing anything, no running, no falling, no playing, she was simply laying at our feet when it started, she acted restless, like she couldn't get comfortable and I could tell in her face that she was not feeling well.  My husband and I checked her mouth, legs, tummy, tail everything and couldn't tell where she was hurt.  Sometimes she would cry when we touched her back end, sometimes not, sometimes we could get a cry out of her if we touched by her ears, ect.  Nothing consistant, so, Saturday morning I called the vet and he got her right in, after checking her all over and not producing a single whimper he suggested she may have had gas and gave us 3 vials of anti-inflammatory medication in case she started again.  Of course, as soon as we got home, it started again and had continued off and on for the past 5 days now.  I don't think it's gas.  We have given her the medication the vet gave us (1 a day) and I have been giving her 1/2 of St. Joseph's baby aspirin for any muscle aches or pain, but honestly, the constant crying for no apparent reason and whimpering when touched is getting crazy.  The kids can't pet her or pick her up for fear of making her cry and I can tell in her face that she doesn't feel well, I feel badly for her but I don't know what else to do for her.  The vet suggested if the pain continued we could run blood tests, do x-rays and perform other tests, but I don't have the money to spend hundreds of dollars to try to find out what may be wrong.  I was wondering if you ever encountered this before?  Or might know of something else might be wrong??  She doesn't seem to limp but does act a little disoriented when she is having a whimper/cry spell.  Kind of like she is drunk a little, it's not extreme or severe but it's apparent to me.  Please offer any suggestion you could think of or maybe a route I might suggest to my vet.  Thank you so much.  She means the world to my family, we love her dearly and hate to see her go through this.

Answer
This is not typical, and I have not encountered this before.  

I, too, would recommend further testing.  

The disorientation is concerning and may be some form of seizure activity?

You can also contact the breeder and ask if s/he has experienced anything like this before in the pups s/he has had.