Unusual Ache/pains above left testicle

Right...this is the first place I've come to before anything else...

For the past few months I've been experiencing a wierd kinda ache or pain towards the back and above my left testicle. Up until now, it only came about at certain times. Now this will sound wierd, so I'm hoping someone can explain, but only after spending a night in with my girlfriend (not sex, just other stuff/fooling around) will this pain come about. Usually once she's gone home. It's not agony, but its there, and it's uncomfortable. Touching and poking it makes it worse, but I can't pinpoint an exact location, just towards the back of it. After half hour or so it will fade away. I can't feel any substantial lumps but when the pain comes about there does seam to be something there slightly larger than normal, but not on the actual testicle, its sort of floating about towards the back or above it. Still nothing precise and nothing I can explain, like I can't call it a 'lump' as such...but I dunno The past couple of days it's sorta stayed with me. It's not as bad as usual but theres something, and I find myself prodding it and moving them about as almost a habit just to try and relieve myself of it. Another thing I thought I'd mention, which might be totally normal I don't know, but I've been feeling those tiny muscle spasms in the same area, like those you get in your cheek or arms/legs etc...Anything to do with it or not? Hopefully someone (probably an expert with all this info I've given lol) can shed some light on my situation? Thanks...