I remember feeling the same, a long time ago! Try not to worry, it is only natural - your surroundings and the people around you will heavily influence who you are. Everyone reacts to change in different ways - you are just feeling insecure and self conscious. You will find a away to adapt, and you will change. Just try to do things that make you feel happy, and stay relaxed. Try something new too! I'll bet that many others around you are feeling exactly the same, though they may not realise it.