Children are very perceptive, more so than many people give then credit for. They feed off of your energy and your mood. It's not a surprise if you woke up in a bad mood that she's doing her best to try your patients. Put yourself in her shoes for a minute, think of how frustrated you are and you KNOW the reason, she has no idea why what's going on. She only knows that mommy's not acting normally and it's quite possible she's scared and acting out. You've described yourself throwing a fit and yet you seem to expect her to behave better than you are, this is illogical.

Call a family member, friend, social services, or CPS. Anyone... when it gets too much you have to be able to walk away to calm down while she is still safely taken care of. Let someone you know that you are at your breaking point and need help. I don't know the nature of your illness that you require medication, but social services have programs available to help "at risk" parents. Sometimes it's just providing daycare for the afternoon to give you a break, others its parenting classes. They didn't come with a user's manual and we've all been overwhelmed at one time or another. Please use resources available to you.

These frustrating days are a part of parenthood and it's very important not only for your own sanity, but for your daughter's well being that you learn some coping skills.