Extreme pressure after intercourse. feels like a baby crowning in labor only subsides when i lay down ?

Pelvic problem?: This symptom makes me concerned about some sort of internal problem in your pelvis or lower abdomen. Even more concerning if any internal pain during sex, fever, or any vaginal discharge. If a new problem, pelvic inflammatory disease (PID, tubal infection) is a concern if at risk for STD, e.g. new or possibly unsafe partner. Several other possibilities as well. See your doctor soon. Good luck!