It depends on what you mean by "feels too big".
Contact lenses have a shape which is described by the base curve number. On the contact lens packets, you will see BC followed by a 2 digit number, almost always starting with 8. This number
controlsControl
Control rx the tightness of the fit on the cornea. Possibly your eye doctor changed this number, because not all contact lenses come in the full range of base curves. You may be noticing this difference. I would call the person who fitted these contact with your concern.
Also, no matter what it says on the box, you should never sleep in your contact lenses.