Hi, Minnie, all you can do is test. You had sex with your boyfriend a lot, his sperm would have been present in your reproductive tract when you had sex on the 7th, so it is really just luck of the draw. Your boyfriend had the edge in terms of quantity and always having had sperm in your body, but the other guy is not ruled out by the dates. And since it only takes one sperm to get pregnant (I assume you are saying the sex on the 7th was unprotected) all you can do is hope the greater number of opportunities your boyfriend had, carried the day.
I do suggest you stop crying and get some sleep. It won't make the question get answered sooner. It will be answered as soon as you get a DNA test, not before, so there is no point in ruining your life in the meantime. Be sure to test with both guys, especially if you get a prenatal DNA test. It can really put the zap on women's heads to only test one guy and then get a negative, they begin to say to themselves "what if the test is wrong?" You need a pair of tests that say one guy yes and the other guy no.