You could put some hydrocortisone ointment on it for a few days and see if that stops the itch and it goes away. If it doesn't go away, or gets worse or looks unusual, seeing a dermatologist is a good idea.

Not knowing for sure what caused the bumps on your face makes it difficult to advise you. There are a plethora of topical ointments/lotions for itch available over the counter. They include Lanacane, Caladryl Clear and Aveeno Anti-Itch Cream with Natural Colloidal Oatmeal. Ask your local pharmacist which one s/he recommends for use on your face. Clean the area gently before applying the ointment/cream/lotion.

If the itching becomes unbearable and the topical applications don't help, you can take 25 milligrams of Benadryl (diphenydramine). It is available over the counter but, be advised, it may make you drowsy. If that doesn't help, either, call your primary care physician and ask for a referral to a dermatologist.

If you believe the itchy bump is due to an allergic reaction, you can try washing and drying the spot with an antibacterial soap. Caladryl Clear does come in a formula that contains an antihistamine for allergies/itching. If preferred, you could simply take an oral antihistamine medication, such as loratadine, (generic Claritin), that does not cause drowsiness. If this is due to an allergic reaction, it should show significant improvement rather quickly. If not, contact your physician if it does not subside.