I received a bj a few days ago and now the tip of my penis is red and there is discomfort. there is no discharge and i dont see any blisters. ?

Herpes? Yeast?: If uncircumcised, maybe a minor hygiene issue; or yeast infection, sometimes transmitted from a healthy partner's mouth. However, there's a chance this is herpes or other STD and you should be professionally examined. Ask your partner if s/he has oral herpes (cold sores). Other STDs are less likely, but still best to check them out. Get seen ASAP for accurate herpes diagnosis & effective treatment