Hi Saram,
No, i dont think your being a nut!!
I was told at 16w he was over 95% she was a girl, then at my 20w i didnt say i knew but asked the sex (different guy) and he said he was pretty sure it was a girl. (god i hope so!!)
I have some pink clothes but most are white or another colour. I was thinking the same thing, so what i have done is i washed one little pink jump suit (that i want for the hospital) and two pink blankets, im also taking one white blanket - just incase. I thought i'd leave the rest of the pink things for when i get home - just to be safe, if she does turn out to be a boy - i'll keep the blankets and suit for my next one (and pray for a girl!!) or give them to friend who has a girl! Although, i have already told DP that if we do have a boy he'll need to run to bunnings to get blue paint as we painted a feature wall pink in the babys room!

Good luck!