Can I be charged 2 months later for **** possession that was found in my vehicle, even though I wasn't charged with it at the time of the arrest?

I was pulled over for a traffic violation, I was arrested andcharged with violating probation on a DWI (obstruction of a highway) charge. The officer found under a gram of meth in my vehicle. He questioned me about it, but didn't charge me with it. Two months later, the arresting officer calls me at home and tells me that he's going to submit the meth and issue a felony warrant for my arrest if I don't give him a name of somebody involved in **** dealing, manufacturing or vehicle theft. Can he do this? The DWI offense was my first and I had it reduced to obstruction of a highway. Thank you