Pelvic pressure

I have pelvic pressure that is intermittent; I started out very bloated with frequent stops to void urine and urgent bowel movements; no blood in the stool or bleeding anywhere else; but now less bloated but pressure still comes and goes; I had a urine culture that came back negative for infection; I also had a full CBC panel to see if I had anything bacterial or viral; it was also negative for this; I work in EMS and I do lift heavy patients; it appears that my symptoms are more exacerbated after lifting someone heavy; I did just recently have a back injury but these symptoms did not appear until over a month after this injury. I was medically cleared by my doctor for work. My personal physician stated that when he did a full assessment with palpation and auscultation with a stethoscope he did not hear anything unusual; bowl sounds were present and no signs of a AAA; he stated on palpation no feeling of mass or guarding; I felt no pain on palpation and when I sleep on my stomach it relieves the pressure; Any suggestions what this can be?