What contraception can I use if hormonal birth control is not an option?

I have a blood disorder (leiden factor V) which prevents me from talking any form of birth control with hormones in it. This is a problem as I am very paranoid about getting pregnant, I would like to have a child at some point, but not for five or six years. Condoms just seem to risky, and diaphragms and female condoms don't work well for me. So I'm not quite sure what to do. I am able to take the plan B pill, and wondered if I can just take it after having sex. Or if there are any other options out there I would love to know about them! Thank you!