Is there anything else I can do to get rid of my headache?

So, here's some background information. I've been having at least 5-7 headaches a week since a little before 5th grade [a little more than 3 years]. But since this June, I've had this one continuous headache. It hasn't gone away. I've tried OTC pain relievers, but they don't help. I've seen a chiropractor, that didn't help. I'm seeing a neurologist, and I've taken three different medicines [Inderal, Topamax, and Depakote ER]. None of them have worked. I got a CT scan in 5th grade, and an MRI a couple weeks ago, the results for both were normal. We did find out though, last month, that I am allergic to a lot of foods, tomatoes, corn, soy, milk, wheat, peanuts, and oranges [the chiropractor had me get the test done, and it was the kind of test where they draw blood and stuff]. It's obviously not serious allergies, or we would've known earlier. So, for about a month, I've changed my diet to accommodate to my allergies. For a while, my headache didn't hurt as bad as it had, but this past week or so, it's been getting worse again. We saw my doctor last week, she keeps saying it's stress that's causing it. I am a perfectionist, and she thinks that's causing me to be stressed and stuff. But last time we saw her, she told me to do yoga. That was really stupid. But, I did it. Only for a couple of weeks, though. It wasn't really doing anything but making me annoyed and stuff. But, it just seems like there's nothing left to do. And it seems like I'm not able to function as well now, because of the headache.