You should keep a food diary and write down everything you eat and drink for one week and be sure to write the right amount eaten and level of hunger. Look for extra snacks and larger than usual portions to see if you may be eating more calories than you think. Check your exercise plan and don't skip any meals.
Take a five pound bag of sugar or flour and put it on each scale to check for accuracy. Otherwise, don't worry that there's a difference in the starting weight. It's the direction you go from there that counts! Thumbs up for working on your health!