Showing or not showing signs doesn't exactly prove anything. The only way to really know is to have a full STD screening done. Also make sure you are being tested for HIV and AIDS. Scary, I know, but better safe than sorry. If the results come back negative then you are in the clear.
Yes it is scary but I feel so guilty that i wasn't more open in the past.
Beating yourself up about it isn't going to do any good. At least you were safe with other partners and up front with your current one. That's a lot more than other people do. Anyways best of luck :)