A reasonable goal is 1,000 mg. DHA + EPA. Those are the animal based Omega-3's that are the most beneficial agents. The flax contains the lighter molecular weight, vegetable world version omega-3 called ALA that the body converts only a small portion of to DHA.
The ALA is of some benefit but is not in the same league as the big hitters.
You cannot overdo any of these Omega-3 components except to the point of getting too many calories from them and gaining weight...and only Bill Gates is rich enough to worry about it. And God knows eating a pound or two of flax a day would take a super-human effort (and NO taste buds.)
Several Tbsps. of flaxseed every day is a good recipe for bowel health. Keep it up.