Any advise for a nursing mom (4.5 months post partum) that has fibromyalgia? I haven't had my medicine in over a year and have severe pain.

Non-pharmacologic. As mentioned, non-medication strategies would be the safest. Physical therapy, exercise, aquatic therapy, pilates, yoga etc. Also consider behavioral strategies such as meditation, mindfulness, breathing exercises, biofeedback. A pain psychologist can help teach these tools.
Magnesium. Good for you for nursing your baby, even with pain. Magnesium can act as a natural muscle relaxant. Epsom salts is actually magnesium and it can be poured into the bath.
Stay active. Fibromyalgia in nursing patients is difficult, because you shouldn't take your typical medicines while nursing. Until you can go back on medicines, you should try to stay as active as possible. Walking will do. Make sure you get nice and "warm" - a light sweat is a good thing. You may also want to consider doing aquatherapy - getting in the pool will take pressure off your joints. Good luck!
Magnesium. Magnesium malate might help you. There are many other natural therapies but it can often be very useful and is safe in doses that will not interfere with nursing. Obviously when you can get better sleep, that will help. We use microcurrent and pemf therapies to help fibromyalgia as well. They are very safe and very effective for many patients.
TENS unit. Besides these good suggestions, acupuncture/acupressure points or a tens unit might be helpful. Wishing you well.
Sacroiliac belt. #fibromyalgia (fm) symptoms include generous pain from low back ; pelvis disorders. Dysfunction of sacroiliac joint (sij) common in those with fm. At boa.Com contribution of sij to chronic low back and prlvic pain discussed, ; special belt advised to stabilize the joint. At quora.Com, i discuss how symptoms of fm can be controlled with natural therapies.