You should expect you will have to apologize and you should expect that you don’t know what to expect. You cannot control someone else’s feelings. If you sincerely apologize, that is all you can do. If he decides not to continue the relationship, well, that is outside of your control, and a life lesson. We rarely learn unless we’re forced to, and most life lessons are, unfortunately, painful. You know the expression: no pain, no gain?
Either way, you can resolve to get some help for yourself. Maybe you could talk to a counselor about what is contributing towards your issues. The better you understand what contributes towards your calling him a loser, the more likely that the scenario does not play out again in the future.