UPDATE on my IRON story. Primary Doctor will not....

Your labs before your RNY may or may not have been abnormal.  In all probability, the RNY is a likely cause of the anemia. Any responsible doctor needs recent labs  prior to surgery to clear you.

Plastic surgery in no way resembles a RNY surgery. It has hundreds of times more tissue that is cut and needs to heal, compared to  lap RNY.  The stress on the body is very high after PS, and anemia makes it worse.

I agree with the above suggestion on the form of iron WLS patients should be taking. Ferrous sulfate has the highest chance of causing constipation and bloating, and is poorly absorbed. Ferrous fumarate (and other forms like ferrous gluconate and heme iron concentrate) have better absorption and lower GI side effects. 

Those who are well-informed about dietary issues after WLS agree that Vitamin C taken along with the iron is the best way to provide an acid environment to aid iron absorption.

Plastic surgery is a big deal.  It's also not an emergency surgery.  "Fixing the fixable" is needed before proceeding to ensure your safety and the best results.

I also had severe anemia before my bypass, and I continue to have issues after, although now it isn't as bad.

Inflammation in the body can use up your iron, and if you have a chronic inflammatory disease, this can make the issue worse.

Ask your primary to send you to a hematologist to treat the anemia.  You should have a colonoscopy and upper GI scope to make sure that you are not bleeding somewhere inside, and the hematologist can give you iron infusions.  They are not that bad at all, but they do take several hours over a few days.  I have had 3 series of infusion over that 5 years, and they have really helped me to keep my energy and then maintain the levels. 

Hopefully, they are checking all your iron related labs, not just hemoglobin and hematocrit.  Make sure that they are checking your iron level, total iron binding capacity and ferritin.  Those things will help a hematologist put together the big picture.

For what it is worth, I can take 6-8 iron tabs per day, plus eat iron rich foods, and never budge my iron levels - I just don't absorb it that well - never have - even before bypass, and I probably never will.  I would seriously pressure the PCP to refer you.