Dogs ear

Question
Last night we were outside playing with the dog-later on I bent down to pet her and there was this huge fluid filled soft bump on the flap of her ear. It couldn't have been there very long. Its not red, I can't see any bug bite marks its not hot to touch-its like a pillow. she will let me touch it, so it doesn't seem to hurt. I gave her some Benedryl and it didn't help at all. It still was the same size this morning. Should I take her in to my vet or ride it out?
Thankyou very much.

Answer
This is probably an aural hematoma and it needs to be surgically corrected.  It is a pillow of blood under the skin and without being fixed, the ear flap may crinkle when it heals.  Often there is an ear infection or some type of ear irritation causing it.