the only sure way I know to lose a few pounds in a few days is to cut off an appendage... and I don't think you want to do THAT!
But more seriously, check that you really are eating what you think you're eating (that is, are you measuring your food?) and try to get enough exercise and then enjoy yourself on Friday, but think about whether you really want to go off plan (I try to stay on plan)...
If you're trying to lose the weight for good then you just need to give it time. Your friends will be thrilled to see you AND the baby.