For the blood levels to be steady, equipoise needs to be administered at least once a week. In men, the common dosage is in the range of 400-600mg while in women it is around 50-150 mg per week.
Thankfully, oregano is an easy herb to dry, and if it's dried and stored properly, it retains its flavor for many months after harvest. For the best dried oregano, head out to the garden in late April or early May.
If you want your Oregano to continue growing more leaves, then yes, you have to pinch off the flowers. The plant 'thinks' it must produce seeds for whatever reason, and after the flowers come, the plant will stop growing. This will also, as you've said, make it into a bushier plant, just like Basil and many others. I'm seeding herbs this week, including Oregano. It's a treat to be able to do that in autumn here.