Extremely bad idea, paracetamol erodes your stomach lining. There's a reason you're not supposed to take it for longer than 2-3 days in a row. That reason is peptic ulcers. Think having your GI tract ruined for life.
(For context, you generally need to take antidepressants for a month or more before you start seeing effects.)
You really need a GP to prescribe antidepressants. If for any unusual reason you can't access this through healthcare (or the waiting list is too long), there *is* some reputable, replicated evidence that passionflower and valerian have anti-anxiety and antidepressant effects. But be safe and do your research first.