Echinacea should be ok, it's great for your immune system and will keep you healthy.
EFA's are both good and not so good. Fats like Omega-3 are great for your heart, but it is also anti-inflammatory, which means that it has the same effect as NSAID's. It doesn't prevent muscle growth to the same degree that those drugs do, but it does lessen soreness or DOMS (delayed onset muscle soreness) from lifting.
Ingesting EFA's is ok, it won't help you gain mass as much as a diet of red meat will, but you shouldn't have any real issues, just a little less soreness that you could be having.