My stool is bright red and i had a bunch of red velvet cake. could that be the cause?

Yes, if the color of that cake is made from beet root or red food coloring. Most of the time, you can tell the difference between fresh blood in stool versus red color stool just by looking at it. Fresh blood does not change the color of whole stool. Only blood from the upper GI tract can change the stool color altogether but the color is no longer red but it becomes black, tar-like.