I was atcked by my brothers wife and pessed charges on her now she has lied and said I hit her and pressed charges on me it wounld be misdemeanor battery.if some how I am charged could I lose my rn nursing license?

I meen my RN LICENSE

Possibly. It would depend on the nurse-licensing laws of whichever state or country in which you are located.

What physical evidence do you have that she attacked you, and what physical evidence does she have that you attacked her? (Not just the word of someone there.)
Hopefully they will not press charges on either one of you.
What were you hoping to have happen?
Next time, if you chip a tooth or your clothes are ripped, sue in small claims for damages, not as a crime.
You can call the license division of your state to ask, but I would let it go.