Sharp pain/left abdomen under ribs/related to sex, physical activity

[idoesntafraids]

Hi, I'm a 19 year old male, and I've got this issue. Sometimes, when I have sex or engage in other highly physical activities I get this sharp pain in my abdomen, maybe an inch above my bellybutton and an inch to the left, as well as a more general pain that switches from my lower left side to my lower right side, and back again. This is accompanied by a visible and palpable protrusion of the abdominal muscle directly under the skin where the sharp pain is located. The pain there intensifies to the point where it's unbearable. Following such an episode, the muscle remains hard and tight and often protrudes for several minutes after; the sharp pain quickly fades but the general pain remains, and my intestines/stomach begins to make noises accompanied by palpable "ripples" in source locations. Drinking or eating enhances the effect. I'd've thought this was merely a cramp of sorts, even though it didn't feel like any I'd ever had if it hadn't recurred on multiple occasions.
Also of note is one particular occasion, during which activity was particularly vigorous wherein my abdomen did not hurt, but instead made a definitive knocking noise accompanied by a visible and palpable spasm in the same area as the sharp pain, matching the rhythm of the activity.

Admittedly, that episode scared me, and I haven't partaken in sexual activity since. Three of the episodes were followed the next day by bloody stools (which I've never suffered before), whereas I simply felt ill after the others. I'd say there's been a total of maybe 10-15 episodes, all within the last 40 days. Also of note is that this isn't a regular thing; I've been sexually active for some time now, with one partner, who has been cleared for any and all STD's. Since and including the first episode, the act of sex feels different; more enjoyable, ironically enough, until the pain strikes. Please help. Thank you.

[idoesntafraids]

Thank you. I'll get myself checked out then. I appreciate your help.

[benthic_man]

You need to seek medical attention. This discomfort could be any one of a dozen digestive issues, and it does not sound like the problem is going away on its' own.
       Self-diagnosis is only healthy up to a point. You're past that point. For your own well-being, you should schedule a medical appointment as soon as possible. It may be that treatment now can prevent serious trouble in the future.

[joshuaty2010]

You know you self rather than anyone. Cause it might you have an appendicitis. To be diagnose properly its time to consult your problem  on your doctor.