Some people cannot handle high B6 doses. B6 is a strange, because low levels in the body cause neuropathic symptoms, as well as very high levels.

Many people find 50mg a day of this is plenty. In the US there were products with very high doses of B6, in the past, but today, the recommendations are not to exceed 100mg a day.

The B12 should be taken on an empty stomach for best results.
Food hampers its absorption. If you have intact intrinsic factor, the food issue is less important. But really you should have had some blood work before that high dose B complex to see if you were low in the first place.

Some people have intolerances to some foods. Gluten in breads etc, is one. Also the nightshade vegetable family can cause odd sensations. (potato, tomato, peppers and eggplant).
Also MSG in foods can upset many people. By avoiding food triggers for a month, and reintroducing them one by one, will often reveal if there is an intolerance present. The Gluten Free diet often takes longer to show up...6months or more, with benefits if it is the culprit.

I am confused as to your description, of a "tomato-like feeling"...I've never heard that before.