What should be expected on VOP after new felony charge?

I am on probation for 18 Months, in Middlesex County, for 1 Felony Possession charge for Marijuana. I caught a new charge in a different county for 3rd Degree Terroristic Threats, to which I plead guilty. I took a plea deal for 3 years Mental Health probation. What can I expect on my VOP for the new charge in Middlesex? I have no other Felony Convictions. The nature of this VOP is going to be for pleading guilty to the new Terroristic Threat charge. What is most likely to happen, based on information provided? Reinstatement to run concurrent to new probation sentence? Reinstatement plus additional probation time? Jail, or probation termination and Prison? Also, most importantly, if probation was terminated and I did get re-sentenced to serve the 18 Months in Prison on the possession charge, what of the 3 years Probation? What happens to the 3 Years probation deal that I pleaded out to in the other County??