It can be VERY difficult as a new nurse, and all of these things you are experiencing and struggling with are very normal. The hospital is a crazy place, and some doctors and nurses get enjoyment out of making others who are new feel like crap and worthless just so they can feel high and mighty and good about themselves.
I worked at a nursing home for years, and just recently started at a hospital. When I first started at the nursing home, I felt lost and like I had no idea what was going on. Eventually though that all changed and I became more comfortable. Now that I'm in the hospital, even though I'm not a new nurse, all those feelings have come back and of course many people treat me like I know very little. It's extremely difficult, especially when you're the type of person who's brain just doesn't work the same way as other nurses, like things don't click as easy. But it does get better, I promise. You'll get into your groove. I'd say give it a year and if it's still not for you, move onto something else. That year of medsurg experience can be very valuable to other employers.
Best of luck :-)