How long did implant bleeding last?

Today is day 25 of a my cycle- day 22 or 8 dpo I had what was very clearly implant bleeding. Day 24 of cycle I got a faint line positive. I have had brown spotting when I white since implant bleeding and today, 4 days later I had a bowel movement and ended up with a good wipe of bright red fresh blood..... I feel like this pregnancy isn’t going to stick? Anyone have a similar experience? I have 2 boys now-3.5 and 1.5. I had a miscarriage before each. 1 at 7 weeks and 1 at 12 weeks.