116 days isn't really over the top in terms of the upper limits on the days.
If she starts to act listless or seems to be trying to push and nothing comes out or any other behaviour that's really really off then I would take her to the vet. Vets can do sonograms but right now the trip to the vet would be too much of a stressor and she might hold off even longer.
Keep maintaining all appropriate temps.... I would mist her daily.... and even put a laying box in.... they seem to really like those... a sweaterbox with some moistened cyprus or even aspen.... that really deep... it doesn't necessarily need a lid....
Over on the boa thinktank we had a snake go 125 from the POS and the litter was totally fine....
watch her closely and be patient, things should turn out alright...
but if you see any radically suspicious behaviour then it's time for the vet...
good luck, the wait is rather painful.... but it'll all be over soon...
keep us updated.