First of all I would like you to give some more information
What is your age ?
IS the problem worsens as day progresses or it remains same?
The problem you are describing may be due to something called as Ocular Myasthenia Gravis
It is a disease of the neuromuscular junction
leading to breakdown in communication between the nervous system and the muscle, resulting in muscle fatigue
. in this disease slight weakness in the extraocular muscles
would lead to misalignment of the two eyes, even a small degree of which could lead to diplopia ( Seeing double). The problem in near vision may be related to weakness of medial muscle of the eye.
You must get yourself examined with neurologist
or any neuroophthalmologist. Once diagnosis is established treatment in the form of tab is available like Tab Pyridostigmine ( Not advisable without checkup). I hope this will help you.