Did you get it done? How'd it go?
I was ecstatic when I finally got my appointment after a couple months of waiting for enough vaccine to show up after I became eligible. I think the advice is to avoid NSAIDs before getting the shot, but okay after, but not sure why you'd need any if it's one of the two shot vaccines, as the 2d shot is where you're most likely to have what sounds like at most a two day flu-like thing. Again, the shot itself you won't even feel. I did get a pretty sore muscle for 3 days, but it didn't prevent me from doing anything, it just hurt, and didn't need any medication. I mean, it's just kind of there and annoying, but it doesn't get worse and again doesn't prevent any use of the arm. I don't think having had covid makes any difference, nor do any of the other conditions you mention. You've had vaccines all your life, this is just another one, and you're doing the whole world a blessing by seeing to it as best as we can you don't keep this virus going. So no prep necessary, just go and it's quick and then you sit around for 15 minutes as they see if there's any allergic reaction, which there won't be, it almost never happens, or you can take your cello like Yo Yo Ma and serenade everyone waiting until they tell you it's okay to go home and you're back to your life. If it's the one shot, then any effects will be felt after that, as there's no second shot and then you're done with that one. You'll be fine.
Most of my family has already gotten it, and I get it tomorrow. So far, no one has reacted badly, including one with diabetes, high cholesterol, high blood pressure, and some other things. The most is a sore arm and some fatigue. Obviously, your mileage may vary. No one in my family had covid prior, which is really a bloody miracle.
Did they schedule your second appt? Is it 3 weeks or 4 weeks after your first dose? 3 weeks is Pfizer, 4 weeks is Moderna. If they say it's one dose, it's J&J. Where are you getting it done? Check their website. It should say it somewhere.
"The day is looming..." That sounds so daunting. How about the DAY IS COMING! One step closer to some sense of normalcy? You're doing your part to help get there? :)
You've already had covid. Whatever happens with this, it will only last a couple of days, and won't be nearly that bad, right?