I have checked out the website, and found it to be a useful library of resources on herbs and herbalism, especially with its comprehensive list of herbs that are searchable according to their medicinal actions.
I learnt that lemon balm has a number of medicinal uses, including "nervous system tonic & relaxant, carminative, sedative", and I noticed that it can be useful for treating symptoms such as "anxiety, restlessness, palpitations, headache, and excitability and also is a mild anti-depressant. It strengthens the brain and its resistance to stress/shock, and lifts the spirits. It has tonic effects on the heart and circulatory system".http://thenaturopathicherbalist.com/herbs/m-o/melissa-officinalis/
I think I can benefit from this herb myself as well, and I will find out more about how to use this herb, which I bought from the plant nursery, before I harvest the leaves for making natural remedies/health tonics. I am aware different herbs work for different people, so I think I will use a bit first to test if it is suitable for me.