Hi Karita,
My DD has been doing this since about 4.5months, I think as long as she taking her milk that is all what matters.
My DD struggles to get out of my arms when I give her a bottle, refuses it, until I lay her down on the settee, head propped up on a cushion, then and only then will she will take her bottle. Sometimes she refuses the bottle until she is laying flat on the floor.