I have strabismius and I had my eyes tested late september. Why is this happening?

What's the problem? You ask "why is this happening"? But what? Strabismus is misalignment of the eyes. If from childhood, one eye will be suppressed and you will not have visual doubling. If of adult onset (usually from trauma, nerve conditions or blood vessel issues) then you will see double. See a neuro ophthalmologist for diagnosis and treatment.