Can anyone tell me what has happened to my supply....

[KirstyDaisyBBandFifi]

Help - I have been pumping furiously since DD was 3 weeks old and is now 6 weeks - suddenly today my supply has dropped from 650 to less than500 mls and I have no idea what has changed - well I have an idea - I forgot to set my alarm for 3 in the morning to pump and I have missed the middle of the night expressing two nights in a row... can this make that much difference and have i buggered up all of my hard work for the last three weeks? If anyone knows the answer please let me know?

Thanks

It might have made a bit of difference, but shouldn't be irredeemable.
What I found helped to get supply back up was going back to little and often for half a day / a day or so - basically pump for five/ten mins every couple of hours, don't worry if you don't get much out by doing this initially - it will come back again.
BTW - I am assuming you are only pumping, and DD isn't directly feeding too? If you are also feeding her directly, then supply will come back much faster if you apply the timing principle to her, rather than using the pump.