Did I cheat?

So I have been with my boyfriend for almost two years and he calls this cheating. So what happened was I had a girls night out because it was my friends birthday this weekend and went to a few bars. At one bar this group of guys comes over and hangs out and we're just talking have a great time. Well one of them asked for my number so I gave him my sisters lol and then we went to another bar and they came with. The other bar was so packed and crazy and that I ended up grinding on one of the guys. Does this make me a cheater? One of my boyfriends friends saw me I guess and I think he made it sound worst then it actually was but I don't think I'm in any kind of fault. I also did not tell this guy I had a boyfriend. What do you think?