I am a couple of years older than you and over the summer, was investigated for a number of symptoms - rectal bleeding, some trapped wind, some weight loss and occasional loose stools (maybe once a week). The specialist said that at our age, cancer, while a possibility, would the last of the things he would be considering, that hemorrhoids were the most likely with IBD also a possibility.

I did not have a positive result on the stool test, but I only got the older test which I think may be less sensitive and the specialist was assuming it was positive and did not think that was anything to worry about. 

Lots of things can cause blood in the stool. I know how worrying it is. I was panicking all summer and even after the colonoscopy (which just showed hemorrhoids and everything else clear), I still had moments of thinking "what if they missed something? Would hemorrhoids really explain everything?" but the odds are still probably very much against cancer.