How am I doing? Do I really only have a chance at low-tier UC's?

I have mentioned here before that I am 15 - I will be starting my sophomore year of high school on the 27th. I had a 4.0 GPA first semester freshman year, and a 3.9 second semester due to a B in one class.

My extracurriculars are:
-Core member of youth activist group in my city. I host our Facebook and Reddit accs. I am a rep for one of our committees. We have a large following.
-One of the first members of NAACP chapter in my city. We are working on starting a Youth Council.
-Will be part of Nursing Workshop.
-Community member is starting Youth Leadership program in response to the work we have done in our youth activist group.
-Girls Inc.
-Mayor is starting Youth Advisory Commission for us (we work with her in our youth activist group,) and will help me gain experience for nursing.
-Mayor wants me to be in a city “Mask On” video.
-Track/cross country. No position yet.
-Going to help develop Ethnic Studies program for schools in my city, working with Board of Education on that.
-Supposed to have internship experience next summer at hospital through Girls Inc.
-Treasurer of Student Government, may run for something greater later on?

Am I alright for colleges? What else should I do in my upcoming years?

What makes you think you only have a chance at low-tier UC’s? A couple of months ago you believed you were destined for community college. Your other threads had some excellent advice. Do the best you can in classes and try not to worry so much.

UC’s only use 10-11th grades in their GPA calculation, so Sophomore and Junior year are where you can to excel academically. Having done well Freshman year, can only help you maintain that momentum. Continue to participate in the EC’s you enjoy. Do not try to do things you think colleges want to see, do the things that are important to you and you will do fine with college admissions.