I am thinking about leaving med school and i need help

So im in my second year of med school, and im terrified of the feeling of wanting to give up. In 2016 had to take a mandatory course to enter my univrsity of choice, after the couse i took 3 exams and passed all three. After that, in february of 2017, i had to take another course and an exam - which i also passed, which got me into med school. So last year was my first year, and now in 2018, im in my second year.
I attended 6 subjects last year and promoted all of them, then 2 more in the summer. Passed all of them with good grades. And after all of that effort and time and pain that i invested into the career, i want to give up.

I dont know where to begin to explain why i want to leave. For example, just today i spent all my afternoon crying my eyes out because i couldnt understand something. i am a very responsible person and very organized, but i feel like with med school i got even worse. I am capapble of putting at risk my health in order to get the job done, i dont eat or spleep, i cry almost every week. I dont even wanna think about going to school tomorrow.
The college im in is very hard, there's a lot of work to do and a lot to study. And i don't think is worth it, if i had the passion for medicine to keep me going, then the tears and pain and lack of sleep would be worth it because i would be looking foward to learning more.
I see how my friends get excited for a new subject and i envy them, cause i dont feel that, i feel frustrated. Like i just want it to end.
And i see all my books, and photocopies, and all the work that i've done and i feel guilty for wanting to leave. I feel like im letting down my family and friends, but mostly me. I feel like i'm letting me down.

I got into med school because I wanted to be a psychiatrist, from the very begining and i still really want to. I want to be that so ****ing much. But i dont think i'm gonna be able to put up with the next 5 years if i keep feeling like this. I am so unhappy. I'm mostly ngry with myself because there's a part of the that want to be a psychiatrist, but i also want to ****ing die.
I've always been the girl with straight A's. Always being the perfect example, and i dont know what im gonna do if i leave. i am so lost.

Honestly at this point i just want someone to give me some advice. Thnaks.

To those wondering, my university is not in the U.K., it's a university in Latin America.
And I don't have there a tutor or someone who I can't talk to.

Sorry I couldn't reaply to the comments individually, I'm still trying to get the hand of the website.

To those wondering, my university is not in the U.K., it's a university in Latin America.
And I don't have there a tutor or someone who I can't talk to.

Sorry I couldn't reaply to the comments individually, I'm still trying to get the hand of the website.