First bad date

So I'm fairly new to dating. I'm 23 and just had my first date this past year ( on Valentine's Day nonetheless). I had a couple dates with that guy and it didn't work out. Then a few dates with a guy back in November. The dates were fun and were pleasant. I was nervous and stuff obviously but the guys were nice. Anyways, those two relationships didn't work out, but ended amicably. Tonight I had a date with a guy I met on Tinder and it was terrible. He was just so full of himself and obnoxious and I found myself making up an excuse to end things early. He wanted to go back to my place tonight and I was just not comfortable with him. So now I'm left with, how do I politely end things? As a guy who isn't exactly beautiful by conventional standards, I've been on the receiving end of a lot of rejections and I want to try and turn him down gently. He's already texting me wanting a second date.