I am 19 years old, and had my first sex with a condom. Everything was good until the 4th day after intercourse, suddenly I had a pain twice on my lower abdomen, or pelvic area. It was very uncomfortable. It stayed for 5-10 mins then went away. The pain is very weird and uncomfortable. It kept shifting from front to back near the anus. I don?t know if it?s from gas or something else related tot he intercourse.