So sorry you are feeling so overwhelmed ! You have a heavy load to carry alone, and having been a single parent myself for 4 years, I hear what you are saying loud and clear !

IMHO, I think it would be a good idea to perhaps have some blood work done - anemia could be causing some of this, thyroid also. If you get a clean bill of health, then I would suggest finding a P-Doc, or at least a therapist. Your moods could certainly be depression, and perhaps medication would help ! Good luck to you !