Try invoking some earth. Go slow with the invoking and do not overdo it, give it a couple days to really show its effects, then increase the breaths if necessary.
Make sure you used proper safety clauses for your jupiter square. Energy when not properly directed, can easily manifest results that would be undesirable. I used to be prone to insomnia and the jupiter squares never affected this in any way for me, so it is likely you used a bad affirmation.
If necessary, the Isa rune can also help for deeper sleep, but do not overdo it with this one as excessive use can make you dull and insensitive. I used Isa in the past to fix insomnia issues and it worked, but I used too much (~40 minutes of vibrating) and had to remove some annoying side-effects afterwards because of this.