My HormonologyTend to of have lousy sleep in your premenstrual Week 4? The problem is plunging estrogen, which can trigger insomnia and restless sleep by making you more sensitive to aches, pains and itchy or binding pajamas and by causing a plunge in the sleep-regulating brain chemical serotonin. So what can you do about it? Try sipping chamomile tea a couple of hours before bedtime to help you wind down, taking a painkiller if you’ve got premenstrual soreness and doing 10 minutes of calming meditation or progressive muscle relaxation where you tense each group of muscles then relax them starting with your toes and working all the way up to your face.