I've been in error with some of these.
XotGD was correct with sleep.
SteveM70 was correct with become ii 'll - he was the first to suffer 'space sickness' in space (though I think many trainee US astronauts suffered in the simulator aircraft dubbed the 'vomit comet')
Spamcan was correct that he was the first to do more than one orbit. Gagarin did just one, and the first two Americans, Shepard and Frisson, flew suborbital missions.
He was also the first to eat in space (the earlier Soviet and US flights being too short). He was the first to take photographs from space, and to take cine pictures. Given that he was only the fourth human in space (if you discount the US rocket plane trials), and the first to be aloft for a significant period, he may well have other firsts to his credit!
xotGD was the first with a correct answer, so the floor is his.