I don't know what it was Dude, it does seem like the lower astral and had you climbing the wall. think of these things like you would as a parasite. in our natural world many parasites exist that we must not let our immune system get weakened so they can enter. the dream is saying go higher, into higher thought. there are no such beings in the higher planes.
if you do encounter such things again, what worked for me a long time ago was to stand still rather than flee..the act of fleeing gives the being no choice but to pursue it's intended victim which is authenticating its existence by fleeing.
1) stand still
2) look it in the eyes
3) u can use a zap or stun gun on it loaded with PUL bullets...lol...
4) you can do the old standby "be gone in the name of JC!" JC is totally amiable to this.
5) you can throw light on it which is making its darkness go away
6) you can give it a sermon. this is my usual way.
love, alysia