I've worn varifocals for a few years now. Last year I took delivery of a new pair (due to slight change in prescription) and found them difficult to see with compared to my old pair.
I was aware that varifocals are often difficult to adapt to initially; my first pair were, but I soon got used to them. These new ones, however, were definitely not right. For example, there was a very sudden change* at one level between distance and middle vision.
Consequently, I went back to my optician (of whom I have the greatest admiration and trust) and explained exactly what I thought was wrong with them. He agreed that there was a problem and promptly sent them back to the manufacturers. They replaced them and they are now fine. My suspicion is that they had not made the lenses properly, mainly for the reason* above (perhaps an apprentice!), but also because I have every confidence in my optician's abilities.
My advice: go back to your optician and explain as accurately as you can what you think may be wrong. Varifocals are very good, in my opinion, but for the money you pay you want them to be right.