I had an anterior placenta with DS. I felt my first movement at 18 weeks - just like a little tapping and it took a good month or so before it got any stronger than that. I think I probably did find all movements muffled compared with what others seem to experience. I had a scan at my OB at 28 weeks and a growth and development scan at 35 weeks and DS was wriggling like CRAZY during both and I could feel none of it (I don't think I would have had any sleep if I could have felt every movement)...... and he's still wriggling now!!!!