Hang On

[Flos Campi]

I really enjoyed the poem! It's a unique perspective on aging, which is in and of itself a more common theme in poetry, so that individuality is all the more important. As a result, I think you could play up some elements of the imagery to emphasize that uniqueness. Additionally, I think the meter could be evened out to make it sound better, although that would not necessarily be a priority at this point for me. 

Hang On
 
In the yard a rope hangs
from a large tree. You maybe remove the period? It seems to interrupt the flow of thought, unless that's what you were going for here - hesitant like the movements of old age? Also, maybe choose a more pertinent adjective for the tree. "Ancient" suggests the large size and also adds to the age-related meaning of the poem. 
used to swing. A giddy feeling
rode your shoulder whispering I don't quite understand the imagery of a feeling riding your shoulder, although this could be my own fault. If you were trying to parallel the subject riding the swing and the feeling riding the subject, this could be made more clear through diction. 
 “higher, higher”.
 
Now you shuffle
with a gait where the weight beautiful and unexpected internal rhyme!
of a troll being dragged
across the floor kicks
at your calves and pummels
every inch of your limbs.
It gnaws at your knees
and screeches all night. Personally, I liked the troll imagery, although I agree that you should describe the troll more precisely so the reader has a better understanding of exactly what the subject is dealing with here. 
 
So you lie awake.
 
A giddy dream swings
from one use of that rope,
to another.