I have a similar problem only my bumps are a little bigger and some of them bleed and scab over. It gets especially bad when i add hair in for a sew in. I went to a dermatologist and she said my hair curled too tight but I don't think that's true. They gave me a special shampoo that she mixed up. It worked ok but I like using taliah waajid herbal cleanser. It's green and to be honest I don't know what's in it but I tried selsum and head and shoulders and this worked the best and it didn't dry my hair out.