Advice from “one and done” people

I got my first 300 mg shot exactly two months ago. When I first got the shot, I felt over medicated. I was stuck on stupid and couldn’t even talk to people. I made the decision not to go back for any more shots. I know I still have a ton of bupe in me because I test myself every Friday (although the line has gotten a little lighter). Also, my digestion is still slow, so lots of constipation. This past week I have had a nonstop runny nose, also some anxiety is creeping in to my life. I don’t want to over analyze every little feeling that I’m getting, but wonder if I can expect even worse symptoms and side effects down the road. From people who have only gotten 1 shot: did you experience withdrawal symptoms? Or was it an easy taper?