The pain might be due to infection in that area. Use topical gel viz dentogel or rexidin m forte gel. Keep the area clean and brush properly. It shall be fine.

Gums surrounding or covering the wisdom tooth usually get inflamed or ulcerated and cause pain when it is time for the tooth to erupt. Auxiliary factors in gum ulceration can be 1. an impacted(tilted/unable to erupt) wisdom tooth, 2. Upper molar being sharp impinging on the gums below. Treatment should include removal of above factors if true in your case. Supportive medicine includes antiseptic or antibiotic gel for local application like Metrogyl DG gel or Rexidin M Forte gel, along with a pain killer tablet after food.

Ulcer may be caused due to the opposing tooth.. as ulcer can be a resultant of injury.. in your case it might be due to the opposing tooth. Check your dentist if you have inflammation of gums at your wisdom tooth due to the growing tooth resulting in pericoronitis,

Pain & ulcer may be due to sharp cusp. Visit a Dentist.

The wisdom tooth in your case is most probably erupting and is the causative source of problem. Yes you can take a pain killer but a consultation with a good dentist is  must