can i be sent a ticket/summons in the mail for driving with a suspended license without being pulled over?

Yes. All the officer has to do to file a charge is have probable cause to believe that you have committed a crime. With the information he had at hand, he likely had enough to form probable cause. Frankly, he did you a favor since most officers will arrest you for this offense. If you just got a summons you at least avoided the inconvenience of being arrested on the spot and having to post bond. You will either have to post bond (if you're charged with Class B DWLS) or just appear in court (if you're charged with a Class C).

Unfortunately, if you plead guilty or are found guilty after a trial, your license will be resuspended for the original suspension period (whatever you got on the misdemeanor possession charge). You may eligible for an occupational driver's license, but your best bet may be to hire an attorney to either take the case to trial or to negotiate a deferred disposition for you (or try to get one yourself). Talk to a local criminal defense or traffic attorney for more info.

Disclaimer: This answer is provided as a public service and as a general response to a general question, it is not meant, and should not be relied upon as specific legal advice, nor does it create an attorney-client relationship.