VERY noobish question here... I have been playing guitar for a year and a half- 2 years and always played sitting. Now that im playing standing it seems completely different. Is it like starting over again or what? Or am i just not used to it and need some fine tuning?

Honestly it will feel weird-it does to most people. Never felt that weird to me but I had only been playing a short time when i made the transition to doing both a lot. sometimes i have difficulty but its not weird.
i had the same problem. just keep doing it and you get used to it really fast, tust me. also what helps is starting off with having the guitar strap shorter, so the guitar is higher up. it's easier that way, then slowly get comfortable with lowering it if you desire