Melatonin can cause weird dreams but sometimes valerin root will trigger some too.
I'm scrolling up reading from last to first..so you may have covered this.
When I worked at the satellite TV station I had the 11 PM to 7 AM shift, would come home change and head off to school until 2 or 4 PM depending on whether I had to do a show (radio news reader)
so getting to sleep as soon as I got home was essential.
There was a police station next to the station and cops would often stop by and shoot the chat with me
'cause they liked me..some knew me from when I worked for the court.
They suggested melatonin which a lot of cops and especially firemen who have rotating shifts use.
It worked great within a half hour of taking either the capsule or sublingual dose, never gave me strange dreams. The problem was that it took me 4 cups of coffee and a couple of hours to fully wake up.
I'd be running 3 TV stations in my sleep.
So I tried valerian, both in capsule and in tea. I got the worst hangover style headaches from both, like my head was going to explode.
What I found helped me sleep restfully and wake up fast was chamomile and/or linden tea.