I have this friend and we're roommates, and I secretly likes her but I don't know if she's lesbian or not..

One day me and her are in our room, and when I saw her about to sleep she remove her bra, my face goes red once I saw her taking off her bra and I immediately ask her

"H-hey! why are you removing your b-bra?.."

I said in shy tone yet worried tone, and I was blushing like hell!