You need to get the results of your B12 tests in numbers.... "normal" is not sufficient. Lab ranges in US report levels of 200 as "normal" and that is now known to be too too low. Even the cut off of 400 is low for anyone with neuro symptoms. Read my thread that I linked for you. Then you will understand, more clearly.

Most doctors do not understand or treat low B12 according to the new information available now about it.

But that is YOUR decision. It is a basic fundamental supplement for your nervous system. And in the end you will be responsible for maintaining it for the rest of your life.

When you get the methylcobalamin replaced make sure you take it on an empty stomach. Most is dissolved in your saliva and you swallow that. It will be absorbed then passively (without instrinsic factor from the stomach being needed) in the small intestine. But if there is food and fiber present, then the micrograms which are very tiny are absorbed into the food and move along past the absorption site and are then lost. So EMPTY STOMACH assures oral absorption. Very little is absorbed under the tongue, in reality.