All perfect praise be to Allah, The Lord of the Worlds. I testify that there is none worthy of worship except Allah, and that Muhammad is His slave and Messenger.
Do not investigate whether or not you had a discharge. You should block the door of whisperers on yourself, because opening such a door leads to a great evil.
Do not judge that you discharged anything unless you are certain, a certainty on which you could swear. Do not smell your clothes, as this is giving in to whispers. Rather, you should act according to the principle, which is that nothing was discharged.
Merely smelling something is not enough as this could be because of sweat or something else and it does not mean that you had a discharge. So you should not take this into consideration. However, if you are pretty certain that you discharged that moisture, then you have to perform ablution but you do not have to perform Istinjaa' (cleansing the private parts) because vaginal moistures are pure, according to the most preponderant view of the scholars, but it invalidates ablution.
If you notice that moisture, and you doubt when it was discharged, then you should consider it to have happened at the closest time. For example, If you doubt whether you discharged it before or after the prayer, then you should consider it to have been discharged after the prayer. But ignore all whispers and do not pay any attention to them.
Allah knows best.