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?

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.
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.