Should I quit?

First off, I'd like to explain that I am not and have never been a quitter. I worked full timebhours all through high school and my pre reqs, and am very head strong. I was positive I wanted to be a nurse, absolutely positive. I researched and went on this website everyday making sure that this was the choice I wanted and for the most part it.is a perfect fit. I am extremely comfortable with patients\residents, ADLs and all the bodily fluids that go with them are no issue for me, and I've been a PCA for years. I even got over my issue with needles pretty quickly and easily gave my first injection. I love caring for people, angry and mean or happy and sweet, and always have. My only issue is meds. I'm comfortable with the common medications, but I am terrified of hurting somebody by giving them the wrong dose\med and I do not want to be responsible for it. My instructors will ask the class general questions and I always feel clueless. If I have the information in front of me I am comfortable but I cannot remember it off of the top of my head. All I ever wanted to do was help people(cliche) but I was originally interested in fire fighting and other fields such as that. I want to care for people, but I feel.like I cannot do anything right in this program. I've missed one clinical and one lab class because it was.switched to a mandatory rather than open lab last minute. I simply want to help.people, but I don't want to.be responsible for possibly hurting them with medication, and as much as I still want to be a nurse, I have decided that at this point in my life I do.not want to dread getting up everyday with no.life trying to get through school feeling like I am doing nothing right. The advice I'm seeking is, should I leave? Is this a sign that i was wrong.and am.not cut out for this? If so, do you know.of any similar fields that I could.be involved in patient care? Any advice would really be appreciated, I feel pretty lost at this point. I never wanted to be in a competitive field, I don't want a big career or to get my masters. I just wanted to wake up, go to a job where I can care for others, and thats that. Please let me know what you think, thanks so much for your time.