Apple Watch Step Counter

hello,

I recently purchased a new Series 7 watch and I really don't have much experience using it. I wear the watch all day to collect health data but the numbers seem very very off. The step counter is constantly counting more steps! I could be sitting down by my desk or driving my watch always thinks I'm standing and walking. The watch is telling me I walk 3-4 miles per day and I don't walk anywhere close to that and like I said it always thinks I'm standing up! Do you guys have any advice? Am I missing something? Also my other question is when I purchased the watch in a sealed box the watches battery was completely dead. Usually apple products come with 30-40 percent battery. Is that something that can be problematic?

Thanks