Should i join the winter track team?

So im in ninth grade (fourteen year old girl), just started going to highschool. Last year i was on the middle school track and field team as a distance runner, and i HATED it. I was the slowest on the team, always last in all races, my coach hated me, and i hated myself. I ran a mile in 8:15, and i was the world's biggest pussy when it came to running (i would get mad if we had to run more than half a mile -_-) So i promised myself i would never join the team again. Over the summer i started running about every other morning. Since school started i now usually only run on Saturdays before breakfast. I am currently up to a mile and a half warm up. MY workout is 4-4.5 miles followed by a mile where i alternate jogging and sprinting. i either walk or jog a mile cool down. At first i did this just lose weight and get in shape, but now i also want to become a faster runner. My older brother is one of the best runners on the team, so he and his coach keep pestering me about joining. I have become a better runner, since i can run for longer and faster. (Today i timed myself and i ran a 8:50 1 1/4 mile, which is bad i know but the weather was really crappy and i ran at a different time then im used to) Ive learned to like running, but i DESPISE running while being timed and with other people. I know that if i join the team, im going to hate is especially since the practices are harder and longer. But i really don't want to regret not joining and look like a pussy to the coach and my brother (its his last year on the team). Should i risk regretting my decision for the entire winter and join, or do i not? Any advice or comments, even if your calling me a dumbass, which i totally understand :), is much appreciated