same situation when i was becoming a junior, except im done it now.
Was it hard?
not for me, i was the same as you i had a good background and i loved math, i also had the same pre calc/calc teacher, the class is not so hard if you actually pay attention, luckily i had a small class with no one i really knew so it was easy to learn and pay attention. i just reccomend you do your homework, as much as i hated it i always did it and it helps ALOT
What is taught?
Well its alot of stuff to just name it but alot of it relates to derivatives and intergals, you like find alot of areas and volumes of graphs using methods involving derivavitives and intergals, its in my opinion easier then pre calc, i hated pre calc alot, but i love calc, there is actually alot of alegbra involved in calc too which i love
How was the AP exam?
I dont take it till the last day of school so i dont know