Should i take the plan b pill after sex? we used protection, but still, just to be more safe? also, is it dangerous if i take it to often?

Not indicated: ... unless you believe your "physical" protection (condoms?) broke. Male condoms typically have 99+ % protection. And yes it is dangerous if you use it "often", though there is no scientific data supporting use after every intercourse. The best way for you to be sure of when the "danger zone" occurs is to chart your ovulation every month and avoid unprotected intercourse then.