When should fetal movement be regular?

I am 25 weeks now. First started feeling baby around 22 weeks. Husband could feel him at 23.5 weeks. I usually feel him throughout the day sporatically, but I haven't felt much of anything for about 2-3 days now.

Just wondering when I should start to worry or if this is still normal at 25 weeks. At what week should movement be consistent and regular?

I have an anterior placenta if that means anything.