Could I be pregnant?

My husband and I have been having unprotected sex lately. I have irregular cycles. So, I’m not sure if we had sex during my ovulation time. But on an average, I get my period around 35 days. Last Period’s first day was 1/8 and it ended a week later. The days we had sex in cycle num are: 8, 13, 15, 21, 26, 29 and 35. Today is my 36th day.

Last Thursday, cycle day 32, I had medium level spotting and next couple of days light spotting and it stopped yesterday. I have had periods where it spots for 2-3 days increasingly and period starts normal. But this time it was otherway around and it has stopped. Also, on 32nd day I had bad constipated bowel movement with abdominal pain, I was fine after that.

Apart from these I don’t have any other symptoms. Could I be pregnant? If so, when would be the right time to take a pregnancy test?