I'd also get liver function tests (These are taken from a blood test, they mostly check your hepatic enzymes to see if your liver's working okay). If you're like me and live in a country without widespread precision blood tests you'll have to do without what's suggested in that website and go for a plain blood test to check your hepatic enzymes, Estrogen, Estriol, Progesterone, Prolactin, Testosterone, DHT, D3, D4.
That said, there's a reason most doctors don't bother ordering blood tests for most finasteride users. The chance to suffer from real, med-induced side effects is extremely low (3%-5% at the most) and they normally stop a while after leaving treatment. This has been a very stressful year and your anxiety could simply be caused by some other reason.