Question re: official letter requesting "no contact"

Quick question:
Does anyone have experience with this? I contacted my lawyer after I left my N to ask for advice because he is so unpredictable and frankly that scares me. In my state, because I was not married to him, I can't really get any kind of restraining order, but if he continues to contact me I can get an anti-harrassment order. So with my lawyer's help I drafted a letter clearly stating my wish for NC. It has a lot of strong language in it. So I got it ready to send two ways, by registered mail and with return receipt, as per my lawyers suggestion. And it seems the minute I got ready to send it, contact from N has completely stopped. I have been holding on to these letters for two weeks and haven't been able to make myself put them in the mail. Since I already have the result that I want, NC, I don't see the point. And I'm a little afraid of what this letter might incite in him. I'm inclined to just hold on to it until he contacts me again. But maybe I'm just waffling because I'm afraid to do something so final.
Has anyone here had an experience with sending such a letter? Does it make sense to send it? If I don't send it am I putting myself in any jeopardy? If I do sending it am I opening up a can of worms? I have had no texts or emails in two weeks.