First PT Session

I had my first session with my personal trainer today and it went much better than I thought, although it was HARD.
He asked me various questions about what I've been doing so far and where I want to go from here, what areas I want to focus on etc, then did my weight and measurements. Then we went outside into the football stadium next to the gym and the hard work started lol.
He had me doing boxing, squats, step ups, arm dips, running up and down the stairs in the stadium, then exercises with kettlebells, with barely enough time to get my breath back between each. Then we went back inside to do final stretches and wow, they hurt!
If nothing else, from this one session I've learnt that I lean my weight too far forward when doing lots of exercises, including squats and running upstairs, don't dip low enough when doing arm dips, and I don't stretch deep enough afterwards which might explain some of the soreness I get. I struggled with one of the kettlebell exercises and was using my arms too much when I should have been using my abs, hips, butt and thighs mostly, so that's something we're going to have to work on, but he said I'd done really well for a first session. I felt fine until I got into the changing rooms, then suddenly my arms and legs were like jelly lol! But I went for a swim for 20mins and then into the sauna and jacuzzi to relax a little before coming home. I DID feel ok, but as the minutes tick by I can feel that tomorrow my body is NOT going to be happy with me lol, my arms are already starting to ache, as well as my butt and thighs and I'm wiped out. We'll see what tomorrow brings, but if you don't here from me for several days please send a doctor with pain meds and a stretcher lol....