Is there any way to make the body produce it's own melatonin?
Melatonin is produced from serotonin, which is produced from 5-hydroxytryptophan (5-HTP), which is produced from tryptophan. I see that you are already taking a supplement with 5-HTP, and I think you also mentioned chamomile, which is the richest herbal source of tryptophan. So you are already on your way.
The big problem though is that melatonin is quickly destroyed in the body by exposure to bright light. So a few things you can do to help with your melatonin is keep lights dimmed around you for a while before going to bed. Same with bedroom lights and bathroom lights. You can use night lights to see where you are going, but I would not suddenly flip on a bright light. I would also avoid TV before bed. If you sleep at all during the day like I do then black out drapes are a life saver.