Iv had braces for 3 1/2 yrs and I got them off when I got my retainer I wore it I forgot my retainer and im gone 4 2wks what will happen to my teeth?

Might shift. Two weeks is not that long, but there is a slight possibility they may shift a bit. When you get home again, try in the retainer and make sure it fits properly. You should have your orthodontist take a look.
Possible relapse. If the retainer is abnormally tight when you try it in, visit your orthodontist for adjustments.
Shame. It would be a shame to throw away 31/2 years hard work. As soon as you can get your retainers back in, even if they feel tight, and call your Orthodontist to check status.