Question

where was all the gases that got condensed after the big bang? if the big bang was the source of creation then how were gases already present before the big bang?

Answer 1

No, the drawback is that atoms were newly formed when the big bang occured. When the big bang took place it expanded so violently that neutrons were forced to join other atoms such as carbon.
These gases further cooled down and formed huge chunks of matter. Some stayed in liquid form while other condensed and formed huge layers such as that can be seen on jupiter.
So, your answer has both no and yes. There is still no accurate prediction of if these gases really did form or not. Quantum physics is the door to all mysterious mishaps!