When were you last evaluated by a doctor?
Have you had any scans or x-rays in the last year?
Are your hands and feet affected?
What parts of the hands?
Thanks for the extra information. A neurologist is definitely the doctor to see. You need to explore whether this is a pattern of numbness in a 'glove and stocking ' distribution that may be caused by a systemic problem such as diabetes, vitamin deficiency or hypothyroidism or whether the distribution is affecting specific nerves and is due to compression of the nerves at the level of the neck and lower back.
You will need a full examination, some blood tests and then either some scans of the back or some nerve conduction studies of the arms and legs.
Depending on the underlying cause will affect what treatment options are available. However as this improves when you stand then that sound like there should be room for improvement with treatment.
If the limbs are going numb when lying down then this suggests either a circulation problem or manual compression of the nerves at the neck and lower back feeding the limbs however the pattern of numbness does not quite match so you need a couple of neurological tests to establish exactly the pattern of the numbness.