This is more a note, in case somebody else spends ages looking for flax seeds or flax seed oil when it’s in front of their face the whole time.
After a good bit of research and a serious amount of wasted time, flax seeds and linseed are the same thing. Linseed oil can’t be used as a dietary supplement, it’s used for softening leather, preserving wood, caulking, etc. No, I didn’t drink any.
However, linolenic acid is the same thing as flax seed oil and is OK for drinking and using in stuff.
Incidentally, if anyone else is in Spain , it’s “aceite de lino” and “linaza dorada” for the oil and seed, respectively. Now if only they had cottage cheese …