valerian is a mild dissociative and sedative. Valerian does help with anxiety. You have to make sure you buy a good brand, one that has to be refrigerated, and may contain both the herb itself and extracts (more potent).
You cannot get good results from valerian or saint john's wort while you take SSRI antidepressants, benzos, or tricyclic antidepressants (maybe other meds too) and it can actually mess up your absorption of both the herb and the chems.