This patient support community is for discussions relating to the challenges of parenting
teens (age 12-17), including physical, emotional, and cognitive development, handling peer pressure, activities & sports, choosing a college, and relationships.
Also make sure she's eating. My daughter has had those times of lightheadedness, nausea, etc. and I came to find out she had barely eaten that day. It might not be a bad idea also to get some counseling for a little while with a counselor who can teach her ways to control her anxiety, etc.
Kids this age want to fit in so badly and it can be an anxious time for them. I'd encourage her to find friends closer to her age and to try sports or after school clubs until she can find something she's good at. When she finds something she's good at, she'll gain the confidence she needs and that will help a lot with easing some of her anxiety. Best wishes.