First of all, it is very possible that you actually immersed on the proper night. It's not as if you always thought the day of the
hefsek counted as day 1. You know that you count
7 days after the day you do the
hefsek, and just because you got confused at a different time while talking to your husband does not at all mean that you were confused the previous time as well. There is no need to be concerned that your child is a
ben-niddah.
You are also not required to perform any tikkun since you are not at all certain that you actually immersed a night early. Your
tevilah during your first trimester rectified any possible error, and you were definitely
tehorah for the rest of your pregnancy.
If you still feel the need to do some type of teshuva or tikkun, giving tzedakah and reviewing the laws of
niddah are appropriate actions.
Guilt can be crippling if you dwell on an incident (which in this case, probably did not happen) and replay it in your mind for months and years on end. But it can also be a positive force if you use it to change and improve yourself. Focus your energies on being a great mother to your baby. Spend more time reviewing the laws of
niddah so you can become more confident in practicing these laws. When we learn from our mistakes we grow into better people.
Please feel free to get back to us with any further questions.
B'Hatzlacha!
