nodoubter

I'll try to make a long story short here. Maybe about 3 months ago I started getting an unpleasant itching inside my urethra after I ejaculated and it only occured AFTER I ejaculated. After finally getting irritated enough I went to an STD clinic to see if I had contracted an STD. Previous to that I had sexual relations with 3 men in a span of 6 months so I figured it was possible. They tested me for Herpes, HIV, Chlamydia and Gonnorhea. But after taking a look at my penis the doctor suspected I had NGU because I was having a slight discharge and also because of the itchiness. A redness around the head of my penis also started maybe a few days before I went to the clinic. So he prescribed Doxycycline which I was to take for a week. I took the medicine and after a week wanted to know if it had gone away so I maturbated and after ejaculating the itchiness had appeared to be gone. But the redness around the head of my penis never went away. They say that Chlamydia is most often the cause of NGU so I expected to have it when I got my test results back a week later but I did not. To be honest, I never really thought I got it through sex. Two peole gave me oral and with the other I had intercourse but a condom was used. I know it's possible to still get it through oral but I'm not so sure I got it that way. Anyways, after learning I had none of the STD's (besides NGU) I was fairly relieved but still wondering why the redness had not gone away. So I had them re-test me for NGU and it came back that it was gone. But I'm wondering why there's still this redness and still after 3 weeks of no longer having NGU? I am still masturbating maybe once a day (it's hard not to) so I'm wondering if this is only adding fuel to the fire here and if I should give my penis break? The only problem I have now is the redness which seems to be red more one day and not so much the next but then back again.

I also read that Balanitis sounds similar to what's going on with me. But I am circumsized. Do you have any ideas,thoughts or suggestions? This is really frustrating me and I really just want to be done with all of this once and for all. Thanks for any help you can give!