My b12 leavel was 293, shouldn't i be treated when i am having symptons. my doctor said level was fine not to worry, but i feel horriable!

What symptoms? Given: mild anemia it is possible that ↑ing B12 might help ↑ Hb some (however more likely: loosing red blood cells/bone marrow status is larger issue). How could you know/find out? Simple: Significantly ↑ intake of B12 by mouth (injections rarely necessary) yourself, spot check B12 every month to verify results till into the near 1,000 range & see if this makes any difference. (Likely MD more accurate.)