It is possible, I suppose, that having sex every other day depleted the amount of semen he is creating (it probably has depleted the
sperm count slightly also, despite the fact that you are not
having sex every day), but in any case, you are not going to be able to go by that particular cue to know if you are pregnant.
When your period is due, you can take an early-results pregnancy test the first day it is due with at least some certainty of an accurate answer.