try writing in the morning if you can, your brain is more active. But you're right, if you only have time at night, write then.
All night spent dreaming.dreaming of anything at all. Sometimes running when I can run or swimming about to drown, brething water. Salty, thick inmy lungs, thin as paper, luminescent in front of the camera..Focus, twisting out the backgrounds fuzzy trees with the birds song fading in reverberation. I guess the worms are sfe, the birds are blinded by night fog so dense I can feel it, brab it, take a whole hanfull of fog wnad wrap it in newspaper like a smelly old fish, or maybe just it's guts. pale red intestines and the bright green lure of a fisherman with a tale of the one that got away. got away, gone to dream in a silver brook rippling water, water I can't breathe but feel. ICy cold in the early spring, the frost on dewy leaves, the warm scent of birch wood burning on an open fire.
Then sit back and find something in there that relates to you. Then begind writing some interesting words around that. Find rhymes for those words, develope a story where does it begin and end and what is the poihnt.
I didn't use spell check to show you that it's ok not to be perfect all the time. Just go with it and the flow will become a few minutes of your day, uncorrected and exclusively you. Your imagination just needs a path wherever that taakes you is fine.