Brief Answer:
Can be a brain or spine problem

Detailed Answer:
Hello,
I have read your complains. Difficulty in walking and weakness can be due to two problems.
First it can be a brain problem or it can be pinch nerve in neck.

Are you also having difficulty in using your hand for eating, or putting sleeper is impossible for You? If answer of above questions is yes then you are having cervical myelopathy. In this disease there is nerve compression in neck.

If you are having confusing mind state, forgetfulness then it can be a brain problem.
I would suggest you to get MRI of brain and cervical spine to confirm the diagnosis.
Till that time, I would suggest you to use a stick for walking so you would not fall and injured your self. Take methyocobal vitamin to strengthen your nerves.

I hope this answer will help you. Let me know if you want to ask any other questions.

Thanks,

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