This guy asked me out i just need to know if im going about things the right way.?

Just say yes!! You've already said he's really sweet and brilliant (and if your mom rarely approves of anyone and she does of him, that's always a good sign!) Take a chance, go for it. If you say yes, yeah you're risking the same thing repeating, but all guys are different, and just because one guy did something jerky doesn't mean any others will. If you say no, you're risking regret and missing a chance with a great guy, so why not just go for it? I hope it works out for you, whatever you choose to do :]