Nice to have found you here!

[liv]

It is very common. The scale does not really always tell the truth. What happens when you have a sudden hard workout is that all your muscles will hang on to water to help them repair and recover and it will seem like you gain weight but it is just water that will come off once the muscles adjust.
I think it is OK to weigh yourself daily ONLY if you know how easily weight will go up and down for no apparent reason. Some people get so hung up with the scale that a weight gain will make them turn to illegal food because they get discouraged.
Are you keeping an eye on your measurements as well?