Milk Allergy?

Ian has sensitive skin like I do. The past couple months (maybe longer?) he's had an eczema rash on both of his cheeks. I've used a special Aveeno eczema cream to soothe it and sometimes it fades a bit but never goes away completely. I started noticing foods he was eating within a couple hours of his rash getting worse. It has come down to milk and milk products (yogurt, etc). When he would have yogurt or milk, within an hour or two his rash would become very red. The last time he had milk was on Monday at breakfast, and today, his rash is almost gone. It's actually the best I have seen it ever. He has also been less irritable AND since he's been without milk, he's been sleeping through the night. Is all of this just a coincidence? We have had HORRIBLE nights for the longest time with Ian waking up 2 or 3 times a night. I chalked it up to teething (even though he hasn't been teething every single day for months) but now I am wondering if it was due to dairy. He normally would have his last glass of milk around 6:30 or 7pm and then brush his teeth and head to bed at 9pm. Since we've removed dairy he has slept through the night beginning with Monday night. I put a call into his doc's office to ask if he should get an allergy test or if I should experiment with cow's milk alternatives (soy). Waiting now for the return call.

Update - Dr.'s office just called. They want Ian to come in tomorrow. The nurse agrees that he may have a milk allergy, especially with the behavior changes. She thinks Dr. Lee will want to do an allergy test or at least talk about changes in his diet. Will update this post with more info tomorrow afternoon.