Tri bike fit vs Road bike fit

I bought a new road bike about a month and a half ago, had it professionally fit, and I had the same issues and you are having.  My lower back was hurting after my rides and I too felt like I was working extra hard.  I ended up taking my bike back 2 different times for some minor adjustments and it made a huge difference.  If you don't feel right on the bike I would take it back and have some adjustments made.

Just my 2 cents. 

Or mark your current set-up by notching the equipment with a sharpie or a knife, and try some fine-tuning on your own. If you really mess it up, the notches will show you where to return the parts you moved.

That's what I think I will do tonight. I feel like I'm using my quads way too much.

Without pictures or more information, it is hard to say. A properly set up road and tri bike should feel quite different and you should feel like you are using your quads more on the tri bike. It will initially be aerobically harder to do the same thing on the tri bike you have been doing on the road bike. I would take that as a sign that something is right with your fits, not wrong.

This effect will take some getting used to. Initial adaptation should happen pretty quickly: 3 rides, 3 weeks and then after 3 months you should feel pretty good.  After that you will continue to gradually get more and more used to the tri position. The power difference between the two bikes will get smaller and smaller. Your back and neck will adapt. You will become addicted to the extra speed you get from the tri bike.  Your taint will harden. Every month and year will get easier to hammer down in those bars. In the beginning you need to trust... and suffer a bit.

It's an awesome process. My general advice is do no micro-manage your adjustments. If you trust the shop and the person who did the fit, THEN TRUST THEM. Give it at least two weeks, three would be better. Then make one small change (if you still feel the need) and again, give it at least two  weeks, three would be better.

Thanks Dave, I do trust the place where I had the fit done. They did my road bike fit and I haven't had to adjust it at all. I will continue to ride as is and see how I adjust to the new bike. Thanks for the info!!