I had two bms that were dark brown water and the second time i wiped i saw blood that was bright and i had fissure a month ago could it came back?

Yes: Fissures can be active again, unless they fixed it. Any irritation can cause it to bleed. However, see you doctor to make sure its just a fissure and not something else.

Possible: Anal fissure is usually painful with the bowel movement. I wonder if your recent flex sig showed possible hemorrhoids, which can be a source of non painful rectal bleeding.