So should I be tested for other B vitamins and folate ?

You can be, but folate is rarely low. Often it is elevated in fact, especially if B12 is low. Folate is fortified now in US foods, so it
is not likely to be low. Sometimes when doctors do B12 tests, they order folate also. But not all of them do that.

A good all purpose B complex with moderate doses, is B-Right.

http://www.amazon.com/Jarrow-Formula...jarrow+b-right

Jarrow has kept up with the research and offers the activated forms now in this nice formula. Many people over the years here have used it (I still do myself) and were very pleased with it. Amazon's price is about the lowest I've seen for it too.
Usually Jarrow is not available at local stores. This gives good amounts of the complex, but far below 50mg or 100mg that most B complexes have. (some people don't need that much and may have side effects from those high doses.)

From what I recall, serum folate test is not a good indicator of tissue concentration. It's more of a reflection of short term intake. Folate in the red blood cells is suppose to be a better measurement. Like Mrs. D stated, if B12 is low, serum folate is likely to be elevated.

We use Jarrow B complex too and Thorne Research Methyl Guard as well.

My breasts will get pains and tenderness when I skip my daily iodine drops. I've been a member of thyroid and iodine groups and iodine has been a huge topic. Deficiency in the U.S. is said to be major. There is a lot of research on this iodine issue. I'm not a doc but have been working with my health alternatively for 25 yrs or more now.