Novalog and Humulog are both rapid acting insulin analogs.
They are intended to do the same thing but are made by two different manufacturers. Some folks report differences in how they respond to each. So if one is not working the way you want you might try the other.
No surprise that you are nervous. Don't worry. You'll get used to it.
Advise? Stick around, learn all you can. This is no cookie cutter condition. We are all a little different. Your Dr. and others can advise but won't ever know as much as you do about you. You have to take responsability for your treatment.