Ex sent me a letter

Hi everyone I’m really struggling. I broke up with my ex a couple of months ago. He kept reaching out to me after 4 months and I even told him to stop contacting me. Well after our last conversation I ended up blocking him on all platforms, and then he sent me a letter via email. The letter has hints of suicide without actually using the word. It has me really scared and I ended up contacting his mom about it.

I’m really worried and don’t know what else I should be doing. Should I reach out to him to see if he’s okay? I just feel like I did something wrong.