Just to put this question into context, recently I have often become very anxious about niddah related question.
Last week after being with my wife I went to the toilet to wash myself. My white Tzitzit were hanging up in the bathroom and I brushed past them before I had washed myself. I feared at the time that maybe I had some blood on me which may have gone onto the Titzit (I often worry about seeing blood after tashmish) and have since then been trying not to look at them in case I see something.
Yesterday I saw that there is a small speck of red on them. I am worried that this is indeed blood from when I brushed past them and since that was after tashmish the normal leniency of kesem will not apply.
On the other hand, my wife is bh around 4 months pregnant, so she probably wasn’t bleeding. Also, she has never mentioned seeing blood after tashmish and I feel that if she really had been bleeding and the red on my tzitzit is blood she would have noticed some on herself as well. (She does try to not look, however).
Is it to ok to ignore this speck of red, especially that I found it a long time after I brushed past my Tzitzit?
That speck could have come from a lot of other places, therefore there is no need to worry about it at all. Additionally, you don’t even know if there was anything on you at the time, plus your wife is considered a mesulekes damim. Therefore there is no need to have any concern about this.