Hindi ka lang! Honestly, a few of us in my mum group had anterior placenta pero nakita pa rin agad ang movements at gender, kaya super blessed ka talaga hehe, yung placement niya doesn't always block the view or the kicks, it really depends on kung saan exactly positioned siya sa uterus. At 21 weeks you're already feeling it well, so enjoy na yan because some anterior placenta mums say by third trimester the movements feel lighter since there's that cushion, but mas safe lang actually because less direct jabs sa ribs lol.