Since you have a Seaquest BCD, sounds to me like you have an Airsource alt air/inflator attached to your BCD. You can confirm this by looking at the unit to see if it says "Airsource" on it. If so, you use the unit to put air in your BCD to adjust bouancy. The unit also functions as a secondary regulator that you can breath from in an emergency should your primary second stage fail or you give your primary second stage to an out of air diver.
The Apex Egress is a secondary regulator, also called an octopus. Normally you would have either an alt air/inflator on your BCD -or- an octopus, but not necessarily both. You should also have another regulator that you will use as your primary second stage. You didn't mention if you have a primary second, so I'm assuming you don't have one.
If you just bought your gear and haven't used them, I'd take everything back to the dive shop you bought them from and show them what you have. They should recognise the problem right away.