Ay oo, normal yan sa pregnancy kaya don't worry too much mama! The tailbone pain and leg cramps are usually dahil sa weight gain, hormones loosening your ligaments, at ang posture changes, a few of us nakaranas nito around that time din, especially if you're on your feet a lot or nakatuon sa isang position. Para sa relief, try warm baths, stretching, supportive shoes, at baka prenatal massage din if you can, pero since you mentioned your previous miscarriage, best to check in with your OB para ma-assess nila properly at ma-rule out anything else, they'll give you safer remedies na swak for your pregnancy. Maraming hugs, I know how scary it is after what you've been through.