So confused! Please help

Before I start off I know the numbers on the scale means nothing but to me it motivates me to continue going. So this morning i weighed my self and I was 172/173lbs. I decided to moved the scale to see if I get the same numbers and I got 166lbs. I grabbed a 10lb weighed and weighed it in both places and I got 10lbs and did the same with my son who weight is 27/28lbs because we just weighed him at the doctors office and he weigh’s 28lbs at both places then I weighed my self again and I got 2 different numbers. I’m so confused!! Which number should I go with. I should be 169 because I’m eating healthy and exercising.