I'm very sorry for your loss.
I don't relate to losing a pet recently, although I did once lose a beloved pet (all pets are of course loveable and special). I could write more but I just want you to know I think (but of course could be ''wrong'') that this is ''normal'' feelings of grief. I suggest allowing all feelings (easier said than done sometimes) .... this helps me sometimes.
Writing here can help also. And of course talking to someone in real life about it.