Perl::Critic is what you seem to be looking for. Devel::NYTProf is what you seem to be asking for.

Critic will criticise your code and NYTProf will profile (tell you where your slow bits are) it.

I am completely self taught and don't know anyone that can point out stupid flaws that I could avoid to make my scripts run better, faster, etc...

The perlfaqs are a good read too. They're very long, so just take them a bit at a time.

update: added the quote and it's answer