Rest of the in-depth answer is here. Hereof, can you put lights and outlets on the same circuit?
The outlet receptacles must be served by a 20-amp circuit. The same circuit can supply the entire bathroom (outlets plus lighting), provided there are no heaters (including vent fans with built-in heaters) and provided the circuit serves only a single bathroom and no other areas.
Beside above, how many outlets and lights can be on one circuit? A maximum of 12 outlets may be connected to a circuit. This may consist of 12 light outlets or 12 plug outlets (not appliance plugs) or any combination of light and plug outlets mixeed, as long as their total number does not exceed 12 outlets.
Herein, can I add another light to existing switch?
Since the existing light is already connected to the switch and you are not adding a light switch, most of the wiring you need will be present in the wall or ceiling. You can wire the new wall light fixture into the existing light and have a single switch control both lights.
Why are my outlets upside down?
Because if a cord or wire were to fall down on a partially plugged in right-side up outlet you would short out between the hot and the neutral. When the outlet is "upside down" in the above situation the wire would touch ground first.
