Pinching sesation in Penis head, guilty feelings or real problem?

[really scared]

I am 43 and went to a Health Spa.  The girl put the condom on with her mouth while giving me head.  We also had sex.  This is the first time in 11 years of marriage that I have cheated on my wife.  A few days later I started having a slight feeling of discomfort in  my penis.  After reading about the symtoms I have examamined and pulled on my penis for the last 2 weeks looking for discharge and have had none.  Now more inside of the head is sore with a slight pinching sensation which seems to come on more when I am sitting.   and of course when I am stressing about my affair, which is pretty constant.  I had a vasectomy about 3 years ago and since have had more frequent urination problems (which runs in the family.)  About 2 months ago I had my first prostate test and exam and the Dr said I was fine and the uritnation problem was just from getting older.  I mastrubate at least 4 or 5 times per week and if lucky have sex once per week.  I have noticed that my semen is not near as thick and clearer.  The girl even noticed that I had very little semen.  Do I really need to be worried about an STD, have I mentally manifested a problem or is this something else to do with the masturbations or other prostate/uretha problem?  Thank you so much for your advice.

[really scared]

Also, there is no discomfort while urinating or during ejaculation.

[daddiesgirlforever]

The more you ejaculate, the less semen you will have. My DH and I notice it to be that way anyway.So if you masterbate every day, of course your not gonna have alot. I would say your probably just overcome with guilt, if you used protection, and it didnt break, your probably fine....Let this be a lesson to you, maybe next time you'll stay home