This commentary is based on my notes after reading The New International Commentary on the Old Testament: Song of Songs, by Tremper Longman III, 2001
Poem 5 (The Cuddle)
v12 While the king is on his couch, my nard gives off its scent.
She is aroused by him.
v 13 My lover is to me a sachet of myrrh, lodging between my breasts.
The imagery of smell implies they are close to each other. She is likely lying with him, with his head on her bossom.
v 14 A cluster of henna blossoms is my lover to me in the vineyards of En-Gedi.
En-gedi is a beautiful oasis surrounded by desolate land.