Any ideas ?

So today is the 24th, on the 14th I had a obgyn because I was hurting bad, assumed it was just a cyst due to my PCOS they wanted to do an ultrasound but then something happened and was rescheduled to the 19th went in got my ultrasound and everything else. Doctor told me I had a blood filled cyst on my left ovary as well as fluid in both of my Fallopian tubes. Was put on antibiotics and was told when my period started to start on birth control to level out my hormones. Was suppose to start my period yesterday and still not here. She said it could be an infection that caused the fluid which is why I was put on antibiotics. I have been really tired and can’t get enough sleep and have since put that on possibly having an infection and my body just trying to fight it off. If I was pregnant even that early they would have seen a sac atleast on the ultrasound correct?