its really something you need to decide for yourself if you want to do it, the surer you are the more fun your going to have.
i did shrooms and the first 2 hours i couldnt stop thinking wow this is the best time of my life, then this kid starts freaking out and my mom comes home with 6 kids tripping in the basement, and everyoen starts saying "holy shit she knows" while me and my friend are trying to chill everyone out and tell jokes but i still had a terrible trip, i was depressed for a good 4 hours and felt like complete shit. It definetly affected me afterwards ( i think more negatively) , now when i smoke weed and i get super high i get really scared (this never used to happen) and it really made weed not that fun.
the whole shroom thing pisses me off too because ive always wanted to try acid and now i know i definetly won't be able to handle it without having a bad time sometime during the trip, so a word of advice: Be absolutely sure you want to do it, and stick to acid
oh and up there^^^ that would be so sick smoking DMT with a shaman