Weird paranormal experiance?

Ok. So me and my friend were walking the dog at 1 o'clock in the morning. Well there is this little...um... I cant explain it. Like and... opening with willow trees. Well there is a tunnel down there. And at the entrance, my friend saw something. It was some weird animal. She wouldnt move. At all. Well we got to looking at it and it was HUGE. Bigger the a dog but smaller then a human. And it kept doing weird things. And on top of that, we smelt a very strong death smell. Like decaying flesh. And the stronger it got, the more mine, and the neighbors dog started to freak out. And the more weird stuff started to happen. What was it? And btw, it wasnt the first.