I feel like I have mucus draining down my throat could this be csf leak come back I had surgery last year?

CSF leak. Hi
It's difficult, if not impossible to tell just based on the symptoms you're describing. Generally, it's unlikely to have a CSF leak without physical trauma, especially after it was repaired, although this depends entirely on the initial cause of the CSF leak last year and how well the repair surgery went. Hope this helps.