How can i see if i am allergic to sandf lies? i was bitten 5 days ago i have around 40 bites that itch. does that mean i am allergic?

Likely: Insect bites often sensitize people and the reaction tends to get larger with each bite. If the lesions remains itchy, try some topical cortisone cream (wrapping the area with Saran Wrap after application may enhance the penetration). Use a cold towel instead of scratching the lesion to avoid infection. Oral steroid may be needed if the problem is severe. Use insect repellant in the future.