The temperatures are fine. Can go down a couple degrees w/out issue.
70% humidity is also fine, provided the cage is a clean one and the snake isn't forced to sit atop moist substrate for extended periods of time. A once over with a mist-bottle is sufficient.
For now, provide a large dish of fresh water.
Regurgitation causes severe dehydration.
Make sure there is some sort of comfortable hide on either end of the enclosure.
As Rachel says, wait a few weeks, offer a smaller than average prey item, leave it alone for a full week.
If it happens again, take it to the vet.