So much on my mind, CNA..?

I have so much on my mind 
Alot of people here at the rehab center want me to become a CNA and work here
Ms.Kay says it would make Mr.Cary so proud of me
My mom says she doesn't think I could do it and says I would hate it
I'm scared I won't/wouldent be able to do it
I want Mr.Cary to be proud of me though
He and Ms.Kay were there for me when my Memaw died, in so many ways 
I was basically living with them for a while
I screwed up, but, they were still there for me no matter what
They took me to church, dinner and other places 
My mom never paid them a cent 
They offered to let me actually live with them and they fully take care of me
I was on a downward spiral and without them I would have probably been in tons and tons of trouble or dead
Most of all they were there for me and made me feel loved 
Mr.Cary was there for me the most of anyone
So yeah I want to make him proud of me but, I don't know if I can make it 
I have two options in doing it either 
wait till I'm 19 almost 20 graduated to do it or get a GED at 18
My school record is bad with grades and behavior problems etc so I couldent get into some big college or anything but im sure my local one would let me in, either way if I'm going to do it I need to start studying soon because it's a lot harder for me to learn things and takes me a lot longer, but, the thing is idk if our college would let me just take the CNA classes I know I wouldent be able to take other college classes, there's no way in hell I could do college math or anything like that
Id need like 75-80 hours of classes then 16-20 hours of like hands on training, I could do those classes in the afternoon after I help with Mr.Cary in a few years but im scared I wouldent pass, you have to take all kinds of test and  know CPR, how to tell if someone's breathing is shallow,normal, too fast, hyperventilating etc, how to do vital signs, know about medicines and all kinds of stuff
You also have to take state certified tests and all kinds of things
I'm scared I couldent pass them
I don't know if I can handle all the pressure of it 
You also have to have Atleast 12 hours of medical education a year while employed as a CNA for several years
I don't know if there's any point in even trying and I don't know if I'm even willing to but I do know I need to figure it the fuck out
Also, what if like halfway through Mr.Cary isn't even well enough to know who I am? Or something worse, which I don't even wanna think about   Then I did all of that for absolutely nothing and it was all pointless and all that work and energy and money was wasted completely
Gosh I just have so much on my mind
And I don't know what to wear tomorrow to go to the mall with my friend I met from prom