help.....what should i do????

hi frnd...im new here and this is my first time experience and i never been with any girl before....
im a student live as a pg and im shy in nature and i dont have any frnd who is girl and there is a girl not in my college and in present she dont have any bf so the day i saw her fiirst i admire her beauty n start i liking her very much , so few weeks ago i went to talk to her i followed her on my bike but when i reached near her suddenly my hands was started shaking and the butterflies start roses in my stomach and all that thing and i dint got enough courage to talk to her so i returned and this thing went for another 2-3 days and finally she got so much angry so called her brother, he told me to stop following her and leave her alone....from that days im scared and depressed too, i love her so much i could die for her.......please guys how should i approach to her....