All your activities are probably harmless short term, but over time can cause health issues and even trigger PVC's. It's unusual, but PVC's can be triggered by vitamins, caffeine, alcohol, and even some food.
It might be prudent to stop the vitamins, alcohol, and caffeine. Lay off for at least 4 weeks. If your PVC's stop or are reduced, great. If not, still great because you are still healthier.
A recent study on fish oil looks promising.