Was diagnosed wit endometriosis n had my left ovary removed I had a regular on time period after jus had sex day b4 my PMS n it didn't cum can I b preg?

Endometriosis. Your chances of becoming pregnant depend on many factors. You may ask your doctor what other findings were discovered at surgery, such as the status of your fallopian tubes. If your period is late you should always consider pregnancy as the most common reason for this to happen.
Sure. Absolutely that is possible. Anytime you are having unprotected sex and miss a period you should check a pregnancy test to see if you are pregnant. Is that the most likely explanation, probably not. Most likely your period is late or maybe you did not ovulate this month and wont get a period.