I Had A Friend Who Is An RN At Our

I had a friend who is an RN at our house and she was saying good bye to my 18 y/o dtr when she noticed a very large/swollen(?) lump on her neck, slightly to the left. The lump is at least 3 inches in circumference. What could this be from? She's not allergic to anything that we know of. Last night we found out she did drink a lot of alcohol. I'm just now sure if what ever is happening could get worse and affect her airway. We live 45 minutes from a hospital. What should I do? Scared mom