2 year old daughter has had hives for 2 months nearly everyday, went to allergist yesterday?

He skin tested her with a toothpick for the top 13 food allergies for her age, and dust mites and everything was negative. I for sure thought it was a food allergy, particularily dairy because she breaks out after eating, and I noticed it after ice cream badly and also pretty bad after a ranch veggie dip. She also wakes up with them pretty bad sometimes. We just can't figure it out. The allergist wants me to give her an antihistamine everyday for 2 months straight and then for a month give it as needed. Well thats pretty much what I've been doing since she started getting them. He wants to see her in 3 months, but its a pediatric allergist that we have to drive an hour there and back for, and the appointment took 3 hours yesterday, which was mostly waiting on the staff, not to even mention gas costs. That is very hard for a 2 year old. If he didn't see anything yesterday, would you go back? She didn't have hives last night, so I didn't give her an antihistamine. If anything, I think I want to make an appointment with a different pediatric allergist an hour away in the other direction to get a second opinion. Any experiences?