I help you smell and sometimes I run when you are sick. What am I?

I have two wheels, but no engine to whiz around. You pedal with your feet to ride me around the room... or outdoors! What am I? Solve the riddle → I end a sentence, but have no mouth. I am a small dot, but mark a point. What am I? Solve the riddle → I have a foot but no leg. I often come in pairs, but one always disappears. What am I? Solve the riddle → I slither forward without feet. I shed my skin and like to show off my new scales. What am I? Solve the riddle → I am round and shimmering, but burst with a blink. You can blow me with a wand, then you see me float, then I am nothing. I drift in the air, light and clear. What am I? Solve the riddle →