I don't know whether or not I'm having seizures

Hello everyone, I have no idea if what I'm having is a seizure, so I thought I'd ask here. I've tried searching the internet, but I keep getting all the same information, and it's not really helping me figure out whether or not what I get are seizures or not. Every so often, I get these weird...episodes is what I'll call them I guess. It used to be several times a day a few years ago, though lately I usually get them once a day or less. My whole body tenses way up, it seems as though I'm in physical pain, like in my chest and upper body, but even I can tell that that's just in my head when I compare it to real pain. Maybe I think it's painful because of how tight my muscles tense up, or maybe because my brain is sending pain signals, but during the episode it seems really, really painful, but as soon as it's over I can tell that it was really nothing. The thing is that I'm completely aware of what's happening. It's easier for me to cope with if I just lay down and let it run it's course, but I can push it down and kind of ignore it (so my body just tenses up a lot), so I'm not worried about becoming a danger to myself or getting one of these attacks while driving/swimming (which has happened before, but I always was able to just slow down and push it away). It oddly seems to happen when I need to urinate, though I can't tell if the need comes before or after the attack, but I've always associated the two together, and while the attacks do go away on their own, it seems like they go away sooner if I go to the bathroom (which makes me wonder if it's some weird, psychologically wrong thing in my head, especially since I can push it aside if I need to). What I mean by ending sooner is that they kind of come in series' I guess? I'll get one tightening, and then my body will loosen up, and sometimes that's it and other times I'll get multiple tightenings before the episode is over. Sometimes it can be minutes or seconds between tightenings. I've had this for awhile, and it hasn't seemed to affect me. The reason I never looked into before was because I thought it was in my head before, but lately I've just been wondering if it wasn't, if it was a real seizure. I just wanted to check and get the opinions of others who know a lot about this kind of stuff. Thanks in advance