Yes the areas are crusty...on her head(she has two scabs that I have been putting Neosporin on), under her chin...actually her whole body is very dry and somewhat crusty. She has lost a lot of her hair all over her body as well.
In a puppy as young as yours, the very first thing I think of for these weird patches is mange (which is pretty common in puppies).
There are actually two types of mange mites: sarcoptes and demodex. In order to effectively treat the mange, you first have to identify which type of mite it is that is causing the problem. This can only be done at your vets office. During the appointment, your vet or tech will take a skin scraping of the affected area and will check under the microscope to identify which type of mite you have.
Demodex looks like this: http://www.fsbio-hannover.de/oftheweek/256/demodex_canis.jpg
And here's some information on Demodex: http://www.marvistavet.com/html/body_demodectic_mange.html
Sarcoptes looks like this: http://www.bayeranimal.com.au/_uploads/images/Sarcoptes.jpg
And here is some information on Sarcoptes: http://www.marvistavet.com/html/body_sarcoptic_mange.html
Regardless of which type of mange mite your dog has, it will require veterinary treatment to ensure that the mites are completely eradicated.
I understand that you(like so many other people) are in a hard financial spot right now. There are some organizations that might be able to help. If you'll follow these links: http://www.speakingforspot.com/helppayingforveterinarycare.html , http://www.theamericandogmag.com/non-profit/resources-veterinary-bills-financial-assistance, you'll find dozens and dozens of organizations that may be able to help pay for you to take your dog to the vet. Also, there are some clinics who offer free exams and other treatments and require that you only pay for medications. If you'll follow this link: http://www.vcahospitals.com/main/offer , you can see if there is one in your area.
Would these mites cause her weight to fluctuate? I feel so so very bad because she just looks sad and although she has energy most times, she stays in her bed a lot, and even though we bath her she has an awful Oder...I just want to cry...