Is it normal to suddenly change your sexual preferrence?

Yes, I have chronic shifts in my sexual preference, it usually depends on my mood.

It's sometimes hard to tell what is or isn't a "phase" until you are looking back at the moment. It seems a bit odd to just wake up and change your sexual preference with no prior thoughts. Nothing wrong with your choice of course, but if it feels right then roll with it.

Yes, always chose the winning team

Completly normal didint do it all of a suddent but i slowly stoped likeing women and slowly liked men im only seventeen but im preity sure im purely attracted to men and im comfortable with how i feel

hmmmm, not sure but whoever u end up being with make sure that they are nice to u and are a good person. I guess it really doesn't matter what sex you choose to be with only that they are nice. I am totally straight and have never switched teams although I did switch from team Edward to team Jacob back to team Edward alot lol. But you know what I mean, Ive never traded liking sexes so Im not sure if you want my advice or not cause Im straight but I think your normal. I dont think being gay or bi makes u abnormal. What I dont think is normal is straight girls who like jerk wads. Just be sure the person u end up liking is kind who ever u may choose. Dont worry what people think ya know. Just make sure your treated right.

When I was much younger, I had a period that lasted for a few years. Where in which, I thought I was gay, but one day it hit me that I was Bi! I've never been with anyone sexually, that I know of. So, this is based on emotional and physical attraction.

I did this, I was sure I was straight and fixed on it. Then suddenly Ifound myself getting attracted to females and looksing at pictures and videos of lesbian porn. I have decided i am bi now, i would never have a girlfriend but enjoy female company.
For example, in a 3sommme, i would rather being with one guy and another girl rather than 2 men.

So other team needed a pitcher and you stepped up. I say normal but a temporary change.