If it is dry or starved temporarily, it is good practice to run the engine without plugs in to ensure the oil circulates properly and fills the circuit. It's not protocol but just a good habit to get into. This enables the oil to (comparatively) gently move throughout and pressurise the circuit.

You did well not to run it too long. When the engine is freshly rebuilt it is also good practice to pack the pump with a denser material like petroleum jelly, just to assist to begin the circulation. I used grease once but have since been told that is a bad idea as the oil does not break the grease down, potentially creating a 'clot' if you like. Also remember to fill the oil filter with oil if you are replacing it.