If you were placed on 3 years probation, the offense must have been a felony. If it was for simple possession, a 3rd degree felony, the violation of probation adds 6 pts to your felony score sheet used by the original judge to sentence you. You will probably not score prison time, however, each individual judge and county has their own general practices for sentencing. If you violated for a technical violation, (i.e. not a new law alleged to have been committed), like for a dirty urine or noncompletion of community service hours, you may be placed back on probation with the same terms and conditions or with the addition of more drug treatment. With any felony probation violation you should assume that jail or prison time is an option for the court up to the statutory maximum of the charge, which should be five years. You should consult with a lawyer in that city.
In Broward County, it depends mainly on the specific judge. Sentences for even a technical violation because of a positive urinalysis may result in a revocation, loss of a withhold adjudication (felony conviction), suspension of driver's license for 2 years, and even incarceration. Or you may just get reinstated to the original term.
Violations based upon new arrests or new law violations are considered substantive, rather than technical, and may face more severe punishments, in addition to penalties associated with the new charges.
Whether your violation is technical or substantive, you can still be sentenced to anything from a reinstatement, to a revocation with a jail term up to the statutory maximum of the underlying offense that got you put on probation in the first place. But again, this varies greatly based upon what courtroom you are in. There are no bright-line rules as to how these matters are governed.
You are subject to the Maximum Penalty under the Florida Criminal Punishment Code. Your attorney should get you an offer from the State prior to any Violation Hearing.