Need to tilt my head to see clearly out of new glasses?

I recently purchased a pair of HD progressive glasses. Details as follows:

Old Glasses:
1.67 plastic progressives with AR coating; worn for 4 years
OD Sphere -6.00, Cylinder -.50, Axis 095, Add 2
OS Sphere -7.25, Cylinder -.50, Axis 085, Add 2

New Glasses:
1.67 High Definition plastic progressives with AR coating
OD Sphere -5.50, Cylinder -1.00, Axis 090, Add 2
OS Sphere -7.00, Cylinder -.75, Axis 090, Add 2

The old glasses had become slightly overcorrected over time as my eyes had improved slightly; something I had not heard of until my optometrist said this was common as your eyes age (I am in my early 50's). Despite the overcorrection, however, the glasses did not cause me any discomfort or eyestrain, other than the fact I had to look through a lower part of the lenses than I would have normally if the lenses were not overcorrected. Despite the overcorrection, once I found the appropriate level on the progressives, I could see pretty much equal out of both eyes.

I have been wearing the new glasses for about 3 days now. There is no doubt the overall vision is better than with my old glasses, as I don't have to tilt my head up as far to see clearly. However, I am experiencing major eye strain especially at the computer or while looking at anything close up.

I tried covering one eye at a time to see if I could notice anything different. If I look straight ahead at the computer screen, for example, I can see clearly out of the left eye. With the right eye, however, I am unable to see the screen clearly, no matter what level I look through the lense, unless I tilt my head sideways to the left. But doing this then skewers the vision in the left eye.

Bottom line - I can't see with clarity at short range while looking at something straight on with the right eye. I have to look slightly sideways.

Do you have any suggestions as to why this is happening? I have been back to the optician and they say the measurements etc of my new glasses are correct (digital measurements were used; a first for me, but apparently 5 times more accurate than manual measurements).

Needless to say this problem is causing me a fair bit of anxiety as the glasses were very expensive and I really need to be able to get them right. As well the eyestrain is so bad, I am having to revert back at night to my old glasses just to get some relief, but I know this is not recommended as it delays adjustment time.

Any advice or help would be appreciated!

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