I'm not sure sedative is the best word. Chamomile contains a natural muscle relaxant of sorts and this does have an affect on the overall neuron-muscular system. However most substances considered sedatives have a much stronger impact on said system. so you could call it a sedative, yes.... but it's not going to "sedate you" per se.
If you are looking for a sedative try the following:
Valerian (stronger muscle relaxant), Lemon Balm and Lady's slipper in equal amounts up to a teaspoon - do not put much more and do not drink this (did I mention you fix this as a tea?) unless you have a day or so you can devote to sleep....
so on a scale:
chamomile = helps you sleep
Valerian = removal of painful muscle spasms and soreness + sleeping
The recipe I just gave = zzzzzzzzzzz ... "dude are you in a coma?"
Lavender? I've never heard of that before. How does it work for you? Would you say it's stronger or weaker than chamomile?
I would necessarily compare them head to head. Lavender helps sooth the mind. the best way to describe it is through the old witchcraft and folk-lore viewpoint of it. It has an affinity with a very dynamic motive mind yet at the same time has calming properties. It's considers a sympathetic healer of sorts.
As to where Chamomile is much more of a muscle relaxant. This is not to say that Lavender is not but that it is more psychological in nature than physical.