billing for ER charges

I'm trying to understand billing practices for ER visit. My wife and I got married about a month ago. The week before, she hurt her toe and we went to the ER. It was very painful and we thought she might have damaged her toe nail. At the ER all they did was put her foot in water with soap and clean the toe. The nurse said it wasn't serious since the toe was able to bleed properly. We got an xray also and it showed no injury. My wife was unemployed and had no insurance then (she was my fiance).
Now we got 3 bills for it. $15 for xray lab. $300 for nurse and $1000 for ER hospital. All from different places. Is it common for the nurse to bill you separately then the hospital? Also, why is the hospital bill so large? For the hospital the line items include "ER CHG LEVEL III MOD 25 $750" and "TOE GREAT RIGHT $145" and "NYS SURCHARGE $100." So what dos that all mean?
The nurse bill is easier to understand basically charging to look at the toe. It's outrageously overpriced for 15 minutes of work and soap and water... but at least its not $1000 like the hospital bill.
So after I understand the bill, I'll have to figure out how to pay it. I read here that people have suggested to apply to medicaid. My fiance had "hudson health plan," a local health plan for people who can't afford insurance. She lost coverage 6 months ago because her unemployment benefits were to large. So does that mean she wouldn't qualify for medicaid either? And if she qualified for medicaid at the time of the ER visit can we apple now, even though she now has proper insurance since she is married to me?