some cramping and pressure is normal, but if the cramping leads to bleeding then it's best to contact your doctor as it may be a sign of miscarriage
. Even at 18 wks I feel cramping
from ligaments stretching and
pressure from the growing baby. it'll continue through pregnancy, but this is normal. Meanwhile make sure to rest, get plenty of sleep, and take the prenatals. Congrats on your pregnancy and good luck!!