Suggest Remedy For Seizure After Sex

My girlfriend and I just had sex, and afterwards she complained about not feeling well. She said her ears were ringing and it felt like she was going to throw up. I told her to lay down and take a couple deep breaths. This seemed to calm her down, but then she started to shake heavily with her legs, and her eyes seemed to roll away a little. It took her a couple seconds to respond to me telling her to wake up and calm down. Afterwards she said it just felt like she woke up, and doesn't remember the shaking. I gave her some water and now she says she feels good. Could this have been a seizure and should we go to the hospital? She said this never happened before.