I am not too familiar with bigfoot construction principles, but as far as I understand, it is a two-piece fiberglass shell (upper and lower). The fiberglass is reinforced with wood (I think) for stability, as it is fairly thin and lightweight and does not support all of the weight on its own.
The walls of your camper have an outer hull - the fiberglass - and an inner hull, with insulation and reinforcements in between. Water/moisture can collect in between and cause trouble without evidence of a leak.
Condensation can and will occur in a camper in winter. When warm, moist air enters the space between inner and outer walls, it will condensate at the coldest points - which are the outer walls. Even without an external leak, a lot ot water can collect that way. Once it is within the wall, it has a hard time getting out again.
Frost can excarbate the issue. When you have moisture trapped anywhere and it freezes, it expands and can create major damage. Often, delamination can occur as a result - that is the de-bonding of surfaces glued together.
Was your camper just on the jacks or was there additional support under the floor? Were the jacks up or down? Having it just on the jacks for an extended time causes a lot of stress on the jack mounts due to camper sway. Also, without floor support, the jack mounts need to carry all the weight alone. Together, this puts a lot of stress on the camper structure.
Is this a problem? Yes! You need to find out what is wrong. If some of the inner reinforcements of your camper structure have come loose or have a wood rot problem, you need to address this. Right now, the fiberglass hull takes a lot more load than it was intended for. As a result, it may buckle, develop stress cracks, or break. None of this will make repairs cheaper or easier. It will not get better if you leave it unaddressed.
Truck campers are not really intended for permanent residence. While it may work fine depending on circumstace, it may not work so well in other cases.
2014 Ford F350 XLT 6.2 SCLB + 2017 Northstar Arrow