Why do I feel panicked for deleting my ex off Facebook?

Ex dumped me just over 3 weeks ago…so I took the plunge and deleted him from Facebook, Twitter and Instagram about 30mins ago. Was sobbing over him as I think he’s seeing someone else and I just realised NO MORE!! Not blocked him tho. My tweets are protected and so are his so I can’t see them. I’ve looked on his Facebook and I can’t see who he’s added as friends etc so that’s good. My profile is on lockdown. I know I’ve done the right thing but part of me is worrying about what he will think?!? Favourite thought at the moment is “what if you never hear from him again? Hahaha!” My mind is warped. Lol. Why am I feeling panicked? As at the same time I feel a strange sense of relief that it’s all over….urgh!