I am 4 weeks 6 days, hcg levels more than doubled over the past 48 hours. I have had little cramping here and there in my uterus area and lower back. I just woke up at 1 am with heavy and hard cramps in my uterus but have no bleeding yet. Can anyone justify to calm my nerves a bit? I just went in for and ultrasound yesterday (infertility patient so more checks) and they said everything looked completely normal.