Not My normal Chart?

So I know lots of people get that 4dpo temp drop, and it just means like an estrogen surge or something? But I have never had this happen in the five months I've been charting my Temps, and this is coincidentally also my first cycle inseminating, should I take that as a good sign or a bad sign? My post o Temps always have a good 4 or 5 days of raising Temps before I get a dip, and it's never this big until way later in my cycle, usually 12dpo. I know it's way too early to tell anything, but with this chart being so different, should I be worried?