Perhaps you looked so confident that no one thought you needed to talk to anyone. Were you the ONLY one walking alone? You said your friends sympathized with you ---so you have friends! That's great! Try not to make one incident a defining event in your life. If you need to improve your self esteem be around people who need you. Helping others is the best way to improve your life as well as others. There will be lots of activities in your school. Try it out. You'll be pleasantly surprised.