Excited/nervous A few questions..

After almost a year of trying to get sublocade approved by my insurance I got the approval yesterday! My goal is to get off this stuff and after doing some research this seemed like the best option. For those of you who have gotten the shot what can I expect the first couple of days? I know some people say tired and over medicated, but will I still feel fine to go to work or do I need to plan to be in bed? How long does it take to level out after the first 300 shot? I’m so excited but feeling nervous of the unknown including how painful the shot is going to be. Thanks for any advice!