Three snakes in the backyard

"I was in the yard behind a house that felt like my cousin's, bending down to pick up a garden hose, and the hose moved. Then it was a snake, olive green, and when I stepped back I noticed a second one by the fence, thicker, darker, just lying there like it had been waiting. I didn't scream. just kept very still. I counted them out loud for some reason, one, two, and then a third slid out from under the porch steps, pale and quick, and I remember being weirdly upset about the number, like three was worse than two. none of them rushed me. They just kept shifting position, closing the space slowly. I tried to go inside and the back door was heavier than it should be, handle slick. my legs wouldn't move right. Someone was calling me from the kitchen, my cousin maybe, but I couldn't answer. Then I was in the kitchen and the floor had a long shadow moving across it. Woke up with my feet pulled up under the blanket, not wanting to put them down."