This will show you pics of applesnail reproduction
. It's from applesnail.net
Is that what you saw your snails doing? If so than you have a male and a female. They will lay clutches when conditions are right. I suggest you make sure the entire top of the tank is covered because the female can "fall" out of the tank sometimes when she's depositing clutches. Also lower the water in the tank a bit so they have room to get their entire body out of the water.
If you read the first line on the above linked to page it reads:
"The apple snail has separated sexes (dioecious) and is NOT a hermaphroditic snail."
It also goes on to say:
"A sex change from male to female (proandry) has been described for some Pila and Pomacea apple snails. In case of Pila snails, the male needs a preparatory aestivation period to become a female, while the Pomacea snails can change sex at all times (at least in certain species). During this sex change, the testis change in colour and decrease in size. The frequency at which this sex change occurs is not certain and not much literature is available about this subject."