Doing my first open mic tonight!

As the title say, I'm doing my first open mic. I'm worried that I am going to spit out my material too fast and have leftover time. What do I do then? LeVe early or try to add lib and risk messing up the little momentum I might have got with my jokes? Also, I get that there is a high chance of bombing. I hope it don't happen of course but I'm not worried if it does

UPDATE: Cause so many asked, I got all my jokes out. Got some decent laughs. Didn't bomb! I missed a few lines I wanted to throw in but they wernt detrimental. I did my full time so that wasn't an issue! Overall a fun experience! Can't wait to do it again!