Sorry for tmi 
In the past I have had bits of tomato skin in my bowel movement, which are usually reddy orange in colour but yesterday I had a bit of darker red (but not massively dark) on wiping (mixed in with wipe ifyswim
) that I initially panicked about but then remembered I had made a tomato pasta sauce on Friday evening with tinned tomatoes and the colour was similar to cooked down tinned tomatoes.
Anyway! I guess I'm asking if tinned tomatoes could be the culprit here? Or should I go straight to gp? I should add that I have been more than once since and all has been fine