They actually told you when they would test you. Your PO must like you or he/she is setting you up for a call in for a random test. Although most PO's will give you 30 days to clean up.

I would recommend staying away from all controlled substances that are not prescribed to you.

How long are you on probation for? If you successfully complete probation did they offer to clear your record or give you an SIS when sentenced?

-EW