Weight GAIN! Help me with the math...

 I've been told to weigh myself only about once a month. I weigh myself every morning just before I get in the shower.  In the past 3 weeks I lost only about 5 pounds total and was really getting fed up. I was ready to call my Doc just to see if I was doing something wrong. Then I lost 6 pounds in the last 4 days. I have no idea why. But I am a bit relieved that I am losing again (for now).