You could go and get emergency contraception today and it may still work for you. You'll be at the end of the time period when it can, so it'll be more like 75% effective rather than the 95% it can be when taken earlier. But it sounds like you really don't want to be pregnant, so that 75% can make a big difference, including for your peace of mind. Do you know where and how to get it?
We can't engage with pregnancy scares beyond this, but know that pregnancy doesn't happen so fast (which is why EC can still work), so there won't be any way of knowing if you're going to become pregnant, because even if you do, you wouldn't be pregnant yet.
You'll also want to look into STI testing in the next month or so, so if you need help finding that, we can help, too.
Did you both need some information on how to use condoms properly, or help troubleshooting whatever you were having trouble with? Also, did this person ask you if he could take his condom off? If so, was it something you said was okay? Something you felt able to say no to if it wasn't okay with you (it doesn't sound like it is, that's why I ask)?
Never doubt that a small group of thoughtful, committed citizens can change the world. Indeed, it is the only thing that ever has. - Margaret Mead