Name That Trauma :: Reader Buffy M. on a Trapped Teen

I was hoping maybe you could help me with a movie title. I have been looking for it forever. I remember watching it on T.V. late at night when I was younger. This was in the late '80s early '90s. I remember toward the beginning of the movie there is a teen-aged girl and she somehow got trapped in a house. She is looking out the window of the room and sees a guy get hit in the head with a shovel or a mailbox. She falls back from the window and lands on the floor. After sitting there she lifts up her hand and there are a few maggots on her palm, she brushes them away quickly.

I could be getting it confused with another movie but I thought at the end she somehow finds her way out of the house but it's like shes crawls out of a drain or something and there is this crazy looking lake or something. She may have been helped by a troll?

Any help would be greatly appreciated!!!!

— Buffy

UNK SEZ: Hmmmm, the guy getting hit with a mailbox doesn't exactly fit but the rest sounds like it could be DARIO ARGENTO's 1985 flick PHENOMENA (although if you caught it on T.V. it was more likely titled CREEPERS). The girl (JENNIFER CONNELLY) being trapped in a house, finding maggots in her palm, escaping through a drain and ending up at a lake all fit. There is even a mutant kid who looks like a troll- although he was not so much trying to help the girl as kill her. Check out the clip below (It's the Italian version) and let me know if it rings any bells!