Honestly, if your question is “can I get be pregnant?” and the details involve “I had sex”, the answer is always, always “yes, you could be pregnant.” I’m not trying to be rude or snarky—sperm have a will and a way of getting around any and all obstacles, into your egg, and making a baby.
However, I, personally, think you may be ovulating if it is very light bleeding. Given the timing of your last period. Some people bleed a bit during ovulation. Even some people who have never done it before can start doing it for no reason and then really never do it again. Either way—get a test if you are concerned about it.