Heavy Steps In An Old Hut

First of all, I'm sorry for any spelling mistakes because English is not my mother tongue and I'm still trying to improve it.

Anyway...on to my experience. I live in Stuttgart (Germany southwest) and this is were it takes place. My city is sourrounded by many vineyards, so my friends and I used to go in my grandpa's old vineyard garden in summer. In the last few weeks, I have only been there with my boyfriend, just sitting between the vineyards and enjoying the view of our city beneath us. Nothing scary and actually quite peaceful.

In that vineyard garden of my grandpa is also an old "barn" or let's call it little wooden hut where he kept stuff such as things for making wine or for garden work but also barbecue equipment. When we wanted to go home, we had to pass this little hut. I suddenly heard what sounded like heavy steps in there. My boyfriend opened the door very harsh and quickly but there was no one there! (it's just one little room, so there is nowhere to hide). Well, we just laughed it off as our imagination.

However, when we returned a few days later, we could hear it again and there was no one in there. As soon as my boyfriend opened the door, the sound was gone.

I decided to go there with my brother and our border collie. He is a very friendly dog and normally all he thinks of is playing and cuddling all day. But as soon as we passed the hut and stood in front of it, he began to look afraid and started growling like he never did before. We heard those creepy, heavy steps again (like an old man walking). As soon as we opened the door, it was gone again. I know, that old wooden barns/huts can make scary cracking noises but what we heard were STEPS. Just like human steps. Nothing sounding like an animal.

After a few days, we decided to tell my mother since this is our vineyard garden. My mother went with us and heard it too. She looked inside, but it was gone again. All she said was "That's weird" but I could see that she felt uneasy too.

Today, I told my grandma about the creepy noises/steps in our hut. She said that my grandpa (unfortunately, he died last September) used to love this vineyard and the little hut. She is convinced that it might be him "returning".

I'm not claiming that this is something paranormal but I'm officially freaked out now. Does anyone know what it could be? Did you experience something similar?

Thanks for reading,

Viktoria M.