Well I suggest not pulling out the dip stick with the engine running. There should be no reason to do it. You can't get an accurate oil level measurement with the engine running. The engine should be off, car on a level surface and having been turned off for a couple of minutes to allow the oil to drain back, otherwise you would likely get a false low level and you might end up over filling the oil which could damage the engine.

It would not be unusual for there to be some pressure in in that area with the engine running and it certainly could blow out a small amount of oil, which, of course, is a second good reason for not removing the dip stick with the engine running....

imho.