Flame- how old are you if you don't mind my asking? I am a urologist and a cyclist- if you are under 40 the chance this is a urologic problem instead of a bike fit problem is close to 0, and the urologist will be a waste of time and $$. See a good bike fitter. If you are over 40 then good idea to go get checked out which will unfortunately involve, or should involve, a prostate check digitally and by blood test. If you end up with the diagnosis of a "prostate infection" be very suspicious about taking long term antibiotics, your prostate might be inflamed but not likely infected and some of the antibiotics(cipro and levaquin primarily) can have some nasty side effects in terms of tendon and ligament damage. Best of luck, keep us informed
Oh and btw that's not your groin, thats your taint.