I'm sorry to hear that you and your girlfriend broke up. The first love always hurts the most. I remember mine like it was yesterday, but the fact is each day that goes by, you'll start to feel a little better. Unfortunately you have to wait, but trust me, it might not seem like it's going to get better, but it will. You'll notice that each day that goes by will see you feeling a little better. Even if it's just a tiny bit, the most imporant thing is you will get over her and continue on with life.
And of course this STD thing is going to be on your mind, especially when blood is involved. Most people don't realize how easy it is to catch an STD like Herpes, for example. The fact of the matter is we realize the mistakes we make after we make them, unfortunately. I don't know how long you were with her for, but if it wasn't that long, you just never know how honest people can be with you.
This in turn makes your mind go wild. What if she had an STD?? What if she had HIV and didn't know?? What if she had HIV and didn't tell me?? What if I accidentally ripped the condom?? These thoughts all come flooding and rushing in, and it's hard to stop them when we feel like we've made a big mistake or done something that could have harmed us.
The best thing you can do is just go get tested for Herpes and HIV and any other STD's or bloodbourne pathogens, and get tested once a year so your mind will be at ease. My advice, and believe me I learned this the hard way, is not to engage in sex with anyone unless there are a couple of things you know for sure:
1. You've both been tested, and you're both sure you do not have any type of STD's. This includes Herpes, and HIV since these are not curable. Be warned: Herpes blood tests can sometimes come back positive because the virus is very common and most everyone has been exposed to it. This does not mean you have Herpes. When our bodies encounter it, the immune systems releases anitbodies to deal with the Herpes antigen, so therefore you'll test positive, but again it doesn't mean you have it.
2. You've sat down and really talked about sex before actually having it. It's alot harder to have a serious discussion about sex when you're already locked in a passionate moment.
3. You both consider the risks of having sex such as STD's, and pregnancy and you're both in agreement what would happen in the event of pregnancy.
4. You and your fiance/girlfriend are both educated on STD's, how they're transmitted, and what risks are involved.
5. You're sure you're going to get married, and you're happy with each other.
It's sad to say that having sex nowadays can actually kill you, and I'm learned my lesson from getting Herpes, and I won't make another mistake again. I don't believe in casual sex or fooling around anymore because like I said I learned my lesson. Remember when sex was safe, and skydiving wasn't? Now it's safer to jump out of a plane than have sex.
All of these things are alot to think about, which is why I'm sure you're very anxious about STD's and HIV. Again, have a full blood screen done, and specify to your doctor that you want to be tested for Herpes and HIV. I know that when you donate blood they automatically test your blood for HIV as well as other things, and if there is anything wrong, you'll get a letter from the blood bank telling you so.
If I need specific blood work done, I go to my doctor. But if I just want to have an HIV test done, I donate blood because it's a free test, and donating blood helps save people's lives.
Hope this helps!