Go to war and kill a man. Watch a live baby being born. Hold your mother's hand while she takes her last breaths. Visit another country. At least watch a movie were REAL horrible things happen, (I'd recommend The Lovely Bones). In the length of your life, a single conversation is irrelevant. In the grand scheme of things, your life is insignificant.

In 100 years, the only memory of you will be buried on the 157,000th page of google. Nothing you do will have any impact on the world at all. In three days, that girl will have been approached so much and inundated with so much information, she won't remember that accidentally said "penis" when you meant "promise" and it was such a minor thing she didn't even bother telling anyone else. It is all totally irrelevant. You can read that negatively or nihilistically, but it means you are free. Don't waste your life fixating on mistakes no one else will remember. You're not regretting mistakes you've made, you're regretting being too scared to even try with the excuse that you might make mistakes.