Help, I have bumpy skin on the back of my arms! I exfoliate and moisturise, nothing helps. Is it an allergy?

I'm wanting to know if anyone else has this prob. I have rough, bumpy skin on the back of my arms, top of my thighs and on my bum cheeks...... help. I moisturise everyday and exfoliate all the time, but nothing seems to be working. Could this be an allergy? Maybe to wheat or milk?? I'm guessing, but it's horrible. Almost like little dry pimples. I'd like to go to a dermatologist, but it's $175 for a consultation alone!!! Any advice would be great. Thanks