Baby seizure in the womb?

Hi mummies, I was sleeping when I felt baby violently shake inside. Google told me that it might be startling reflexes or otherwise seizure. My gynae appointment is in a week and I'm just wondering if this is normal at all? My baby is super active but the movements seem weird a while ago (feels like hands and feet were up vibrating). I'm currently 28 weeks btw, thanks in advanced for your reply :)