My CAT has blood in her stool, i recently moved from the other side of the world to canada...?

I moved from a warm climate near the equator to canada where it is -21 at times but my cat NEVER goes outdoors shes always warm...i give her dry food same as before but now been seeing blood in her stools shes about 7 years old she was perfectly fine at the previous place, she doesnt seem sick at all should i just change her food to wet food if so which would be best IAMS? i think its the change of place but im not sure.....i take care of her alot i cant imagine her having worms or anything else and shes 7 so i dont think its cancer etc...or i would have noticed it before...maybe she got worms some how over a flight but im sure they spary the love caro area