approximately how old are your Oscars? When Oscars lay eggs, it's very obvious which one is the female, her egg tube will stick out quite a long way. the males sexual organ is a little less obtrusive, it's a little spike that is sometimes quite hard to see. Obviously if the eggs hatch after 36 hours, you'll know you do have a male and a female. However, they are often take several attempts before they are successful, probably due to them being inexperienced. I've noticed that the female seems to know what she's doing, the male isn't quite sure. If the eggs stay white/cream in color, you'll know they are not fertilized, if they change to a brown color, they are fertilized.
Let us say the situation tomorrow, you should see some change if things are going okay.
