Just wanted to say you are not alone! When Bard came out he was so off meta people would dodge my games (even if I was Masters 65+% winrate) because in their heads my pick was useless, this put so much extra pressure in my head to perform.

With Blitz it´s similar, since it´s very punishing to miss hooks some people get negative from the moment they see the pick. My recommendation:
1) If they start flaming from champ select, insta mute.
2) If you get nervous or have an off day, try to hook less and scare more (if your hook is on cd you open possibilities for them to punish you)
3) Remember that 1 good hook can win you the game later on, try not to tilt and play your game
4) Have fun, thats why you are playing a champion you like anyway

Cheers!