I started on a tele floor, the first year I hated it, but pretty sure I would've hated any floor. I think it's because we are new, don't know what we are doing and for me it was a mini anxiety attack every shift I had to go in. And that was on the tele floor for me, so I can imagine any ICU is slightly more intense for a newbie. Then somewhere just pass year 1, something clicked. I know I don't know everything, I'm okay with it, but I'd go into work and think, well, if I don't know, I'll ask, I can only do what I can do and stopped beating myself up for not knowing what I didn't know.
Man, the first year...or maybe more of nursing is a trial by fire. They told us that in school, but you think it'll be fine, I adjust well to other adverse situations. Nope, for many it really is a hot mess of learning. It's intense, we are caring for sick people and we feel responsible for them and worry about messing up or not knowing what we don't know. The pressure is pretty intense. Then suddenly, for a good amount, something just clicks, you go in and you think, well, this patient load will be a challenge, but I will do what I can do and I will ask for help if I need it.
I understand your anxiety. But if it is getting crippling, consider moving to a different unit, somewhere you will be happier and see a doc, there is no shame in asking for help. Just know each unit has it's challenges. I would say try to hang in there till you hit that year mark, but if you can't, you can't and that's okay. Just remember with your ICU experience, even if it is just a year, you will be a hot commodity down the road when you would like to move elsewhere. If you can hang tough in ICU, it qualifies you to be able to do nursing almost anywhere.