Yes, I am sure this is why you're struggling, since you've noticed your sensitivities and have had a similar previous reaction.
Have you tried switching when you take your 20mg vs. your 10mg pill?
IOW, if you take the 20 in the a.m. and then10 in the p.m., try reversing that schedule and see how it works. Or, if you can split your 20 mg, try that, so you are taking 3, 10mgs as before.
With some adjustments and time, you will become accustomed to this new regimen eventually.
Until then, use your coping skills and hang in there!