Hello, I have an issue that I desperately need addressed

I have bouts of extreme itching on my scalp, parts of my neck, and the shoulders and upper back (When I first begin working out or exercising, when I exert such as times when I need to lift something heavy, or when I blush or become embarrassed). This is a very debilitating condition because the itching that occurs is extremely intense. At times, the itching gets so bad that I feel that I need to gauge my finger nails into my scalp or skin or that I need to pull my hair out

I am a 21 year old, healthy, Asian Male. I have allergies and I take Zyrtec and Singular to control them. I eat a normal diet, drink lots of water, and I try not to consume too many snack foods or greasy foods. I get regular exercise and about 6-8 hours of sleep nightly

I have gone to many doctors about this problem and none of them seem to be able to diagnose me. They tell me that they have seen patients that have had extreme itching but that none of those cases have been similar to mine where the itching is exclusively in my head, neck, shoulders, and upper back. I have been to an allergist and had an allergy test done. They told me I was very allergic to dust might feces and mildly allergic to a type of grass

Please, I really desperately want to stop this condition. If anybody could help diagnose me so that I could find some way to treat this condition and find relief, I would be eternally grateful

Thank you