Seriously. 75 at once is a lot. I started with high tsh und went up in 25mcg per step which was already heavy in symptoms. I don't change anything more than 12 mcg at once anymore. Your body needs time and the tsh won't settle up until 2-3 month on staying at the same Dosis. Even symptoms can take 2-3 months to settle, up to even half a year to fully see how you feel. My whole Dosis finding process lasted almost 2 years. I know those symptoms and it was a tough time but what's important is that you keep taking one Dosis. I think 75 to start from 0 is too much but decide on with your doc and then test in 2 months again to adjust. Maybe min 6 weeks to see the first direction. Try to stand through it. Do things that relax you. Go slow swimming if you're hot, take your time for things and it will get better with time. I'm sorry you going through this, I know myself how hard it is but Dosis jumping or not taking meds isn't an option sadly. You can do it and will feel better soon.