Is it normal that i think my boyfriend prefers his ex's looks over mine?

I've been with my boyfriend for about 6 months now and our relationship is great, except for the fact that I feel inferior to his ex in the looks department. Yes, my boyfriend tells me i'm beautiful and this and that, but I still feel like he prefers the looks and stat of his ex. I don't like to wear shorts because I'm personally not comfortable with showing my legs. I have tons of scars from scratching my skin too hard and my thigh to calf ratio is very much off. I have thick thighs and no calf muscles. I hate my feet because I have fall in arches so it makes my ankles look odd when i'm in open toed shoes. His ex has a nice body and style. She wears very feminine clothing and I wear a t shirt and leggings.
The main reason why I feel this way is because earlier in our relationship (probably before we were even dating) I asked his straight up if he preferred his ex's looks over mine and he just told me to forget about it. He pretty much just brushed it off to try to get me to stop talking about it. By him reacting in that manner it makes me think that the answer is yes, and that he does prefer the looks of her over me.