She said it’s small

I 16m was finally gonna have sex with my girlfriend and everything was going fine she was leading (I’m a sub) but then when she unzipped my pants and brought my boxers down she eyed my dick weirdly I thought it was probably cause she was shy. Timeskip she rubs it to make it hard and then just when she was about to suck me she said I can’t do it. I thought she was uncomfortable and wanted to wait and I told her we can she said it’s not that I’m uncomfortable it’s that u have a really small dick. I have a 6 inch dick please tell me if the size is alright brothers and what should I do.