The outcome depends on two things more than anything else: what the violation actually was and how the sentencing judge responds to it.
Probation violations range widely in severity. Missing a check-in appointment is treated very differently from a new arrest or a failed drug test. A technical violation with no new criminal conduct gives the judge more flexibility to be lenient. A violation involving new criminal behavior is a much harder conversation in the courtroom.
For a first-time violation with no prior history, judges often have options short of revoking probation entirely. They can add conditions, extend the probation period, order a short jail stay as a sanction, require additional programming like drug treatment or anger management, or issue a stern warning and release. None of those outcomes are guaranteed, but they are all on the table for someone who has not violated before and whose underlying offense was not severe.
What works against leniency is the judge's perception that probation was not taken seriously. Courts view probation as an act of generosity, an alternative to incarceration that the defendant asked for and received. A violation signals that the generosity was not honored, and some judges respond to that personally.
The most important thing right now is getting an attorney involved before the violation hearing. A lawyer can communicate with the probation officer, present mitigating circumstances, and make the strongest possible case to the judge for a sanction short of full revocation. Walking into that hearing without representation is a significant disadvantage when the outcome could mean serving the remainder of the original sentence behind bars.