I Have Bumps On My Head. Seems To Be Under

I have bumps on my head. Seems to be under my skin though. Super itchy but definitely not lice as I've had several people check for me. It's pretty painful & seems to follow a vein where it started on my neck. What's causing this & what can I buy over the counter to relieve the itching??? Please help! Thank you so much for your time Dr.