I too am changing careers for nursing and I can't wait to finish! ALL jobs on the planet have negatives - there is no perfect job and it is wrong to think that any job ever will be.
I don't know if I'll help but I'll try. It is soooo super hard making a decision to do something for the rest of your life - and maybe you shouldn't put that pressure on yourself. Is it children you want to teach, or adults? Would being a nursing instructor be an option for you?