What you described sounds like the WILD (Wake initiated lucid dream) technique. During this technique, you keep your mind awake while your body falls asleep. During this process, you will experience sleep paralysis, a feeling of heaviness and paralyzation usually accompanied by Hypnogogia. Sleep paralysis is the gateway to inducing BOTH lucid dreams and OBEs, but if you don't want to induce an OBE during this state, you don't have to. You can willingly choose to enter a lucid dream or an OBE in sleep paralysis. As for hypnagogia alone, hypnogogia is not so much used to induce an OBE. Hypnogogia is usually used to form a dreamscape and enter a lucid dream. Hope this helped!