Kind of Scared for Sophomore Year of High School?

I went to school last year with a friend who completely stopped talking to me after the first couple of days and just ignored me even at her grandparents house. My mom and dad didn't like the high school and liked the one where my brother is going better. So I'm a sophomore and switching schools AGAIN. I'm a shy 15 year old girl. My brother is a senior and won't be at school until 5th hour because he is doing a college thing in the morning.
Things I'm nervous about:
-I'm shy and didn't talk much at the other high school. But I want to come out of my shell this year, i just don't want to get made fun of. How can I come out of my shell?
-At the other high school the first day was a half day but at this new high school the first day is a full day. I'm worried about where I'm going to sit at lunch? My brother says the lunch room is pretty full because there are only 2 lunches. I know people aren't expecting of new kids sometimes so where should I sit and what do I do if no one wants to sit with me?
-I got anxiety last year because of my "friends" mother who yelled at me and treated me bad. I also didn't like Spanish and was scared every day to go to that class. So how can I calm down?
-I have to ride the bus this year unless my brother gets his drivers license sometime soon. Is the bus bad to ride? I have a iPhone and iPod to listen to music and play games on.
-Last question… I know teachers don't count freshman late the first couple of days because they are new to learning where to go… But I'm going to be a sophomore, so do teachers count you tardy if you are late?

Sorry its long and I know I've done this whole high school thing but it was different because I was a Freshman and I had a half day the first day.

You worry too much, just smoke some weed and go with the flow. <3