If my LMP was May 25/2013 and my dute date is March 1/2014
When did I conceive?

Impossible to know to a precise date... take you due date... go back 9 months... then conception happened anytime from 2 weeks before that date... to 2 weeks after that date. Meaning there is a 28 day window it could have happened anytime in.

Conception was probably some time in June. But when in June would be just a guess. Anyone you had sex with during June might be the father.

Depending on how they base your due date as well. They usually place you 0-day to the last day of your period and start counting on that. So based upon that you can probably place conception sometime after that date.

Another thing to consider is that conception and implantation doesn't need to occur at or around the sexual encounter. You could have had a one night stand on Friday, conceived on Sunday during mass, and implantation could be another week. So even going back from the implantation or conception date can be misleading.

You can only really guestimate unless you only have sex one day a week at a precise hour.