I went back today. Same clinic, different doctor.
Initially i thought i'd made a mistake as she started off with "it's the gold standard, he's done the right thing, he's trying to rule out the important thing first blah blah" Actually she must have said 'gold standard' 4 times.
But then she relaxed a bit and opened her ears and decided that i needed an iron supplement, try a milk free diet (i was unaware how detrimental cows milk is to iron absorbtion), lemon juice and salt (weird), and some hormone related blood tests, and of course an ultrasound and a referral to a Gyn.

Still think i should have the gastro referral and scopes, but admitted i should probably wait until all the other stuff is investigated!