Nice foot! Although I have always been into men's feet, I don't know if I'd ever participate in tying someone up to worship their feet. Usually, my partners are into my fetish and are delighted to have me lick and suck their feet and toes. As long as you enjoyed your experience and didn't feel violated, I guess you can count yourself lucky several men want to worship your feet, even though what happened to you can be classified as assault/abuse. The fact that you're straight but still enjoyed the experience, that's something you're gonna have to work out with yourself. Gay/Straight/Bi, they're just labels. My advice to you: Do whatever makes you feel good, as long as it doesn't hurt anyone else. Personally, I'd be open to allowing this to happen again, except without them having to tie you up...unless that's something you're into
Good luck, man.