Maria F. answered 03/30/19
Experienced bilingual international business manager and translator
Dear Graduate Speaker,
I would suggest a phrase such as "I totally misused the freedom I was given" or "I absolutely abused the freedom I had." If I may add a little bit of advice on public speaking (especially in an academic setting), I would try not to use your original phrase that includes the word "crap" in it. It is too coloquial and conversational (and gentle swear word as well) for a formal speech such as the one you will be giving. It may be tempting to use it to sound funny or friendly or even "stronger" as you said, but again, since you are asking here in this forum, I would dare recommend that you keep that phrase for after your speech has been given, when you leave the stage or podium and are among close friends.
Hope this helps! Congratulations on your upcoming graduation!
Maria V.F.