I take it this is a wall adapter, Their voltage tends to drop quite a bit as you load them up.
Just do as Soerren says in you other post.
How much amps or Milliamps does your relay pull when energised???
All of the other components in your circuit will work fine from about 3.5V to 18V, it's only the relay that needs a closer tolerance on your voltage
I haven't looked at your circuit since yesterday and I got a head like a sieve but you may find that a diode or two will be enough to drop the voltage to a level your relay will be happier with. You may not need them at all.