Thank you for writing. Asking for help is often the first step in making things better. That being said, there is a limit to what I can do with a letter. You say that a lot has happened to you in your life. It could be that you’ve been coping as best you can but that something tipped the balance so you are now overwhelmed. People who get upset and cry easily (when that isn’t their usual nature) are often people who are emotionally full to the brim. Something little happens and the emotions spill over. It’s like a glass of water that is full all the way to the top. The final little drop isn’t really what makes the water spill. It’s the accumulation. The last drop is the “last straw.”
It’s also possible that there is an underlying medical issue going on. If you haven’t already, do see your PCP for an exam. Explain the emotional roller coaster that you’ve been experiencing. Ask that she check medical issues before recommending that you see a mental health counselor. You don’t want to miss a medical condition due to an assumption that a 17-year-old girl is just going through adolescence.
If the medical exam comes up empty, then please do consider seeing a mental health counselor. From what you wrote, I don’t think you are suffering from a mental illness. But it may be that the events of your life are overwhelming your ability to cope. If that’s the case, a counselor can help you figure out if there is a way to avoid or manage situations that you don’t have control over and can coach you with more effective ways to deal with the challenges of life.
I wish you well.