They are kinda hard to tell apart, unless you have had both - real vibrations you get when WILDing, and different feeling you can get in different parts of body when your body is deeply relaxed.

Normally, WILD/OBE vibrations stop if you move. So I'm leaning towards your sensations being from relaxed body.

But go ahead and explore them. Continue to WILD after you get them and see what they really are. Or after they are over, try and stand up/roll out of your body to see if you are in a dream already.