Hard lump forming on side of head above right ear two days ago, hurts to touch/lay on, cause some headache and hurts to open jaw all the way.

Infection?: I would worry that you have folliculitis or an abscess in your scalp. This is probably a difficult area for you to see, but if it is red, warm, and painful, it could be infected. In this case, a health provider needs to see if it requires drainage and/or if you need antibiotics. I would recommend seeing a health provider soon.

Possible abcess: A new mass that comes up suddenly and is painful to touch could be an abcess. This needs to be evaluated by a physician and may have to be drained.