I'd use them without hesitation.
Short answer: Smell them. They're probably fine. 3 months at fridge temps isn't long enough for the AA% to change all that much. I'd use them with no worries, but I'd freeze them next time. I've used similarly old hops with no issues.
Longer answer: On Jamil and John Palmer's show where they interviewed Glenn Tinseth about bittering, one of them said that he regularly uses hops that have been in the freezer for a year without adjusting the AA%.
Hops are rated with an HSI, which is the AA% they'd lose in 6 months of storage at 68F in an open (not vacuum-sealed) environment.
Typical values are in the 25% range, so a hop that's 8% AA would be at 6% AA after 6 months sitting in an unsealed paper bag on the kitchen counter.
For every 27 degrees Farenheit that you lower the temperature, aging is cut in half. So in a fridge that's 35F, you'd expect the same 8% AA hops to be down to about 7.2% AA after 6 months.
Of course, you only did 3 months, so the same 8% AA hops would be more in the 7.6% AA range (they'd lose 5% of their alpha acids).
But remember, that's if they were sitting in the fridge in an unsealed paper bag--if your hops were still in the vacuum sealed mylar bags you ordered them in, then oxidation will be much slower. I don't know by how much, but assuming they're in the realm of a 25% HSI, you're looking at less than a 5% change in alpha acid percentage and possibly much less. And remember, oxidized beta acids increase bittering, so the actual change in bittering capability is always lower than the change in alpha acid percentage.
