Am I doing something wrong?

Throwaway for privacy issues… So I bought the helix syn and have used it twice. I put it in watch my desired porn or browse my desired reddits and just kind of sit there and relax. I do the contractions and eventually go faster and faster. I get a really good feeling that is hard to describe but it feels great and I try to focus on that. Both times I have had a regular hands free orgasm where I ejaculate. Im guessing this isnt a prostate O or a super O.(Not sure if there is a difference) Both times I stopped after I ejaculate. Do I need to keep going after I cum? Or should i be doing something different. Basically I am contracting my muscle and feeling it push against my prostate which feels amazing, but I am not sure if maybe I should be doing something different?