Am I dumb? Or are they lying?

So I get this all the time but I never notice when it happens. My friends tell me all the time boys are looking at me, like after the fact and I’m like Wutt?? No. I have few examples to say. We went to rent a uhaul and my was talking with the guy getting the info and everytime I wasn’t looking he’d look at me. Then after the fact my aunt points out how much he was staring at me, I never noticed 😂 then yesterday I was with one of my friends and she was telling me than this dude was looking me up n down and looked at my ass and licked his lips.... like wtf why do I never notice or are they just lying. I literally am not attractive. I’m fat.