After one week of antibiotics for a tick bite, it still itches and it's a little red and firm, what should i do?

Steroid: Rub in a steroid cream. You may have a tube for poison ivy. Otc Hydrocortisone 1% is weak but may be enough. Don't be afraid to rub in several times a day. No need to wash before or after. If not ok in a week, see a dermatologist. Avoid antiseptics and antibiotics.If you have Bacitracin or neosporin do not use on this. Peroxide or alcohol will make it worse. Do not use a bandage.

See doc: It is possible that the actual tick bite site has become secondarily infected with skin bacteria and may need another type of antibiotic to cover this infection.