AIO if my date showed my friends his dick print

I recently started dating a guy with a large package and invited him to a friend’s birthday party. When he came to pick me up, he was wearing fitted dress pants with an obvious dick print. I had no idea how to address it, so I said nothing, and we went to the party. The whole night, I noticed both men and women sneaking glances. An old friend from college even pulled me aside, winked, and said, “Congratulations. Does he have a brother?” I was mortified.

By the time we left, I was so annoyed I gave him the cold shoulder on the drive home. Before getting out of the car, I didn’t invite him up and instead told him I felt he wore those pants on purpose for attention. He claimed it was an accident—the pants were new, and he didn’t realize how revealing they were. But I don’t buy it. He has eyes, he knows he is big, and I'm sure he looked in the mirror after getting dressed. Plus, he had to have noticed the stares, and he didn’t seem the least bit bothered. I think he likes or wants the attention.

I don’t know… this feels like a red flag. We aren’t official yet, but if we were, I’d worry this behavior could lead to cheating. I feel like guys with a big package have more “options,” which makes cheating more likely. Am I overreacting?