Bright pee sign of pregnancy? Or vitamins?

I’ve been on prenatals since last week of April. Currently on cycle day 18. We TTC around ovulation time (didn’t test for ovulation just did couple day the week of assumed ovulation. Well today (cycle day 18.) I’ve been peeing more frequent and my pee has been a brighter yellow. Even tho it’s our first time trying, could use be a sign of pregnancy? Or is this a sign of vitamins even tho it’s already been 2mo on them.

Internet kinda says both. Was bright pee a sign of pregnancy for you?