Penis swollen under the head suddenly, no longer can get ere

Last night after a few days of not masturbating, I finally had the chance to do so. I'm single, 21 and have been single for the past two years and haven't had sex in a years time. Last night for the first time I had a problem "After" ejaculation. Everything went fine, perfect erection, no problem at all and after discharge and cleaning up. I noticed a little pain in my testicles and my pelvis area itself. I looking down to check it out and there was this plump fatty like swelling just below the crown of my penis. Usually I would stay erect or semi erect even after preforming my acts, but now after waiting a few hours, i couldn't even get it erect any more, let alone feel the pleasure or trying to tease it into erection. I slept a whole nights sleep and tried again this morning, usually I would wake up with "Morning wood" but nothing, only the familiar swell under the head of my penis. I tried all morning to see if I could get erect, looking at what I would normally look at, and even other things and still nothing at all. My groin hurts a bit, I never had a problem like this before in my life so this is scaring me a lot. This morning I also kinda noticed that he urine was also kinda just dribbling out instead of a full jet stream like normal, this only further worries my case. I cant get into the doctors until two days from now, but I was wondering should I go to the emergency room right away, or could I get a little help here. I want my erection back, and I want to know why it suddenly wont come after tears of having not a single problem at all.

Justin, M. PS: Thank you to any one who answers this, it means a lot to me.