Repairing shower floor

Have a 30 year old ceramic tile shower floor (1" tiles). Somehow 1 tile came out un-noticed and has loosened others, resulting in 36 tiles that popped loose when pried. Subfloor is concrete and all mastic/thin-set has been removed. After everything dries thoroughly am I in for any problems by simply replacing the old tiles (all cleaned off)and re-grouting the whole floor?

If you have cleaned the tiles and the floor, sanded both to remove contminates, then clean both again, you should be fine.