Why does dip stick show overfull but no oil will drain?

I changed the oil in my 2002 Toyota Sienna yesterday. When I was done, I checked the levels and the dip stick showed it to be overfull. I should have stopped before adding the 5th quart, but I didn’t.

So this morning I pulled the drain plug out to reduce the oil level and hardly any oil came out. After maybe ¼ of a quart, it went to a steady drip. I put everything back together and ran the engine for five minutes to warm things up, then when I pulled the plug out, NO oil came out! However, the dip stick stills shows it to be overfull!

Did the oil get pulled into a part of the engine where it’s not supposed to be and now it’s being held there by vacuum? I admit that I only understand the basics of combustion engines, but I’ve changed my own oil before and never seen anything like this. I was just trying to avoid any problems associated with overfilling the oil.

Any help would be very much appreciated.