From experience you know in your heart quite quickly when your drink has been spiked.
For god's sake, how much minimising can we squeeze into 30 posts? That was your experience. Many others have different experiences. I was one of John Worboys's victims and, like 60 other women, didn't even realise until I saw the documentary and memories started coming back. I also had my drink spiked with ketamine and had no fucking clue what had gone wrong. I felt like crap for a week after that.
Some geezer last weekend was buying me triples without saying. I knew he was, because I felt drunker than I should have (luckily, I have the alcohol capacity of an aircraft hangar, but he was still a dick.)
Heyho, if you're an habitual drinker then you know how drunk you 'should' be under various circumstances. You're saying something was wrong, so it was.
Have another look at this before you minimise it again:
he was worried that i was so drunk when we did anything and he should have been a gentleman and gone home but "he didn't want to".
He's TOLD you a decent man, a 'gentleman', would not have fucked you (or 'taken advantage' of you) that pissed ... and, knowing that he wasn't behaving decently towards you, did it anyway because he wanted to.
That's not a nice thing to say or do, is it? Given your other concerns about his weird boundaries, I'd say swerve him from now on.