I am really good at dosage calculations, so if you would like help with that, please feel free to email me. I may have a different way to do them than you were shown in class, and that helps if you don't understand a particular way of doing a problem. I don't even study for the calc. exams, and I always do fine.
As far as pharmacology goes, I had a difficult time too, but found the easiest way for me to study drugs was to make notecards from my notes and supplement them with stuff from the book. For instance, I would take a category of drugs we were studying and write that on the front. On the back, I would write the drug names in that category that we were studying - this helped me to learn what fit into what categories. For individual drugs, I would write the name on the front, and on the back write things I knew we'd be tested on, such as onset, peak, and duration, action, and side effects. It takes a lot of work, but once the cards are made you can just flip through the deck any time you have a couple of minutes to spare. I only got a B in the class (which is about what others made), but I have learned so much more since that class by being in contact with the really commonly prescribed drugs in the clinical setting. I was worried at the end of pharmacology that I had not learned enough to make it through the rest of the program, but I've had no trouble since then. So, I would not stress out too much over the actual class.
About your daughter and bedtime - I'm not a parent, but I would suggest going to bed early with her and then waking up early and stay up. Sleep is a little different with every individual, but I have found that getting up and going to sleep again just makes me really tired the next day.
I'm sorry to hear your mom has lost her job. That is a really stressful thing, and I know this sounds easier said than done, but have faith that everything will be okay, and it will. God never gives us more than we can handle.
Let me know if I can help you out!