Spinning again

I took my second spinning class again today. Loved it! The instructor was different than the one before and the class was totally different than before. I'm really tired again from the class, but the butt kicking also feels really good. The competitive side of me comes out during class. I'll feel really pooped, but I don't want to let up and let the instructor or anyone see me slow down or sit down or in general look like I can't do it. If was that tired working out on my own, I would easily lower the tension or stop completely. I need to the class environment to really push me.