Migraine before labor?

I got a few migraines in the first trimester from the hormonal changes but haven't had any since. Today I woke up with an awful headache that has progressed to a migraine with nausea. Could it be another hormonal change suggesting labor could be close? Two weeks ago I was 1 cm dilated and 80% effaced, I've recently lost mucus plug and have lots of low pelvic pressure.