What Causes Spotting And Frequent Need To Urinate?

I have notice when wiping after I pee only there has been very light blood (like light days when I am on a period--mostly towards the end of my period). I had my period a week ago and it was normal. I am having no pain nor burning at all. I have notice that I need to go more often. I am 36 years old and had 3 children. I also have notice lately I am very stressed, tired, and been eating like crazy. I know for a fact I am not pregnant due to surgery reasons.