I had a series of fillings from November-January. They were all doing very well. Some minor discomfort when I ate and had cold water. It went away foe the most part. Yet, for the last few days my teeth started to ache again. It started as just one hurting... and now, about 25% of my teeth are aching all of the time, regardless of the circumstances. Should I stick it out and see if it improves, or set up an appointment now?

Set up an appointment. This should not be going on.

I agree with your first answer to see your dentist, or a different one. Something is happening, and I wouldn't wait. I had the remainder of my teeth extracted in 2004, and got dentures... not saying that is what you should do!
But, some bone kept coming through a coupld of months after, that had to be removed. I didn't know at the time what it was, it just hurt. Yours is different, and hopefully it won't be anything serious. Good luck.

I can't speak about multiple fillings, but my teenage daughter had a filling done by a new dentist, and it hurt every time she chewed on that side. I took her to my own dentist; he redid the filling and it was immediately fine. Seems the other dentist had made it too high or dense or something - not totally sure, but it was night and day difference when it was redone.