It might be gas. When I overeat I get this too. I heard that it might be gas, but I am not sure. Once after not eating for like two days I ate a whole bunch of lasanga and then I started shaking. I am not sure if you would call it a seizure or just whatever. It wasn't violent but just my whole body shook and it was extremely weird.
Personally I am really trying to stop eating to much, but ironically after not eating for two days really shrank my stomach or something to if I ate anything it felt like I was over eating and I just felt really wrong. But that is how I came to realize that I am not really meant to go well with dairy products or meat. So eating veggies fruits and nuts really feel alot better and my stomach doesn't feel like it will burst and I don't get pains. But I am not sure if that is the case with you. So pretty much I have to become vegan which isn't all that bad. I found some really awesome vegan cookies which I am utterly addicted to.