Home scales are notoriously unreliable - try to stick to the scales are your WW meeting, gyms and doctors offices!
And keep in mind weight fluctuations throughout the day, and even throughout out the week e.g. if you usually have a big night out on friday, of course you'll be heavier for the next day or so!
Try to stick to weighing in just once a week. I can empathise with the temptation to constantly weigh in, but it's not a great thing to do - I got to the point where I was weighing myself every couple of days at home, and so actually threw my home scales out!