Had my 1st PRP treatment 10 days ago. Now have bumps in the treated area and it itches. My forehead is swollen a bit.

hello. I have thinning hair. I've had my first PRP treatment 10 days ago. Now I have a couple of bumps on my scalp in the treated area. the scalp isn't red but the scalp is itching (perhaps because of the bumps?!). My forehead also swelled a bit. I contacted my doctor and he said it shouldn't happen but if I itch I should use baby oil. Is it normal what I'm experiencing? What do you suggest? Sincerely and thank you very much Inbal