Hello Welcome to HCM, thanks for posting your query...
I read your question completely and have understood it well..
Well, to be frank you shouldn't worry.
Post
pregnancy, for atleast 3 months there's absolutely no chance of conception.
There are various articles supporting this data.
It's called natural
contraception..
So, if you have had baby last month which means within 3 months of delivery then you should be tension free..
The hormones play a vital role In fertilization of women's egg..
So as you said, even if semen enters inside, you need not worry..
Enjoy your post delivery days with baby.. Forget that worry, no need to visit the doctor. I've seen many such cases..
Take care, God bless..