Hi. At this age you may have too many expectations and when things don't go in right way which u have expected you get sad easily. This leads to inconvenience slowly followed by loneliness. But though you are a silent person dont completely try be away from people. Have friends talk to them . Understand wat others would like from you. Build your self confidence.you should go out and mingle with all. Dont have negative thoughts . Try to tell Ur problems openly to someone. There is no problem in it.