I am so sorry that you are itching so badly and feeling like bugs are stinging you. A lot of us have that same sensation.
The fact that you can rub off the freckles, leads me to think that you have mites and this is some of their feces. Yuck!
Please join our forum Invisible Bugs crawling on skin? Strange sensation...
There are hundreds of us on here with similar symptoms.
See a dermatologist. I didn't want to spend the money but am glad I did. I went to have one spot looked at and he removed 17 pre cancerous things from my face..... It was worth it.
I don't know if you have ever had chickenpox, or what your age is, have you investigated Shingles