You can take ghusl right away. Whatever is discharged afterwards doesn’t require ghusul but requires washing it off and making wudhu.

I am unable to take ghusl e janaba soon after sleeping with my wife.  I have to wait for 3-4 hours to do so.  This is because I see sticky fluid discharges from my private part if I try to take shower.  It is unlikely that it is seminal fluid but prostratic fluid and its amount is very little.  What should I do so that I do not miss prayers. Take shower right away?