For some reason the formatting's gone funny on this site for me, so I can't 'like' Cherie's & Walkin's advice. But agree. Except that if she's lame in all 4 not likely just laminitis. To clarify... Metabolic/systemic laminitis doesn't discriminate between the feet & does indeed affect all four. But mechanical laminitis(from physical stress, etc) can affect only fronts, and commonly back feet are much healthier, fronts already compromised, which is why the symptoms are commonly worse in front feet.
Sounds like it's quite acute, but hopefully you've caught it early & her feet are otherwise in good nick so she hasn't/won't actually founder(as in mechanical changes that can follow the inflammation).
Yes OP, the first thing I'd do is ring a good equine vet. When they x-ray her, get them to mark her feet, particularly point of frog & dorsal wall.
In the meantime, I would ensure she has soft/yielding footing, or tape foam or polystyrene to her feet, to provide further comfort. Do not try to force her to walk anywhere unless absolutely necessary at the moment. Hosing her feet if they're still hot/inflamed can help her comfort & reduce the damage. I'd also feed her only soaked & drained(to leach out sugars, if it isn't low NSC grass) hay for now & treat her as an insulin resistant horse, at least until proven otherwise. Because unfortunately sugars are not lower in hay than they are in grass.
I would definitely not shoe a laminitic/foundered horse. Peripherally loading the hoof walls when the laminae are already so stressed/compromised is not a good idea. The walls need to be relieved from pressure, not put under more. But the horse may need protection/support for her feet once she gets over the acute stage. I would suggest boots with foam pads, Vettec Sole Guard or casting(Trinity seems to be quite experienced in that) as 3 good options. Of course, there are a couple of different schools of thought & many vets will recommend shoes. So it's a matter of doing your homework & learning about the different options & what theories are behind them(eg. shoeing does usually have a quick palliative effect)
Some sources for further info... www.hoofrehab.com www.ecirhorse.com www.safergrass.org