1. Don’t count yourself out. On anything. Ever. We all have our strengths and weaknesses.
2. You’re young. You’re starting out. It’s an exciting and scary time. Don’t worry if you don’t yet know how your life will go - no-one does!
3. Passion and meaning can come with time. There are entire branches of life people discover well after your age. For me, I was quite a few years older than you before discovering some things that are great joys to me and a huge part of my life. And some years later I am still finding new ones.
4. You say you’re no super genius and yet you’ve got yourself a valuable internship and possible job? This is much better than the alternative, getting it by being a super genius! Trust me when I tell you that hard work matters more in the long run, and you’ve shown you can do it. Lots of people can’t or won’t. They hit a wall when their ability doesn’t let them do things easily any more. You won’t hit that wall. You’ll just keep going.
5. On the point about relationships or family (I forget), again see points 1 and 2. It’s hard to see now but you are just getting started. Be positive and proactive and you never know who you might meet and where it might lead.
Good luck to you.