sick?

Question
I own a baby red-eared slider and recently, it's been kinda strange. When it comes up for air, it looks like it is dizzy and bobs its head or something like it is dizzy or something. I feed it tiny krill because it refuses to eat anything else, even though i have tried 3 different brands. Is it vitamin deficiency? By the way, my mom refuses to take it to the vet and to buy the proper equipment. My dad might buy all the stuff later this weekend.
Also, its been living in the same small box with my other turtle and they never had a problem like this before...
Is it too cold? Because I once accidentally left it outside in its "excersise" cage so it could get some exercise and it was kinda cold out. I think it might be getting better because it doesn't seem too dizzy as the first day when i remember to put warm water into the box.
Diagnosis, please?

Answer
There is not enough information there to make a good diagnosis, but it sounds like things are not going well for your poor little turtle.

When there are multiple care issues, we generally have to work through them all before we can figure out any medical concerns. You already know things are not good, but...

I don't like seeing 'exercise tanks'- the main tank should be adequate. Switching back and forth adds stress. The main tank's water should be big (minimum of 10 gallons of water per inch of turtle), warm (75 to 80F) and clean (big filter system). There are some cheap ways to accomplish all of this- starting with using a plastic storage tub instead of an aquarium.

In most cases, once the temps and water are OK, the feeding should get easier, and once eating and temps are fixed, other behaviors should become normal.

A good site for others ideas would be
http://www.austinsturtlepage.com

A helpful forum is http://www.turtleforum.com