First thing is to calm down it's NO big deal at all. This happens to people on a daily basis. Your shoulders can handle 3cc's regardless. Most of your problem is irritation to the prop i would guess and maybe the enanthate, especially if it came out of a 50ml Qv bottle or certain over seas individuals. In the future try other things before running and taking antibiotics. Yes they work but become less affective everytime you take them, and this isn't a problem you want to run across when your really sick and need something. First try echinachea, it's a natural antibiotic and has worked really well for me in the past. I used 2-3 capsules the first dose and one cap every hour for like 4-5 hours after that and maybe some hot compress's and it worked fine. If that doesn't work then try some tetracycline. This is used more for skin reactions like acne but is mild on the body, but strong enough to clear up the proplem. Cipro works but its really strong and over kill on the body.
The only time you will want to drain an infection is when it becomes and abcess. This is a point when antibiotics are necessary(maybe) and drawing out fluid/blood will need to be done. But chances are this won't happen. One way to fix this is to rotate your injection sites so there isn't alot of repeat. Your quads can handle alot of cc's but there is a slight problem or one that I seem to run into alot. There are alot of veins, nerves that run through there and it becomes really easy to hit one or add pressure to them. Don't get me wrong, I like to inject quads, but in various amounst from time to time. I generally put the big ones in my biceps or shoulders. Good luck with cleaning this up