What Causes Headache And Uneasiness During 41 Weeks Of Pregnancy?

my daughter is 41 weeks pregnant and has lost her plug all week end. She isnt sure if she is feeling labor pains or just over reacting. She has a really bad headache right now and says she isnt feeling right. she does have a doctors appt tomorrow. Our doctor is 45 miles and we already went with one false alarm. I guess we are wondering if this is probably the real thing or another false alarm