Can I apply to have my record sealed if I have a previous drug conviction that was sealed?

Maybe. If you have only one prior drug conviction that was sealed under Criminal Procedure Law section 160.58, and now you seek to have a different conviction sealed, and the total convictions sealed amount to no more than one felony or no more than two misdemeanors, you may be eligible to obtain sealing of the additional conviction under Criminal Procedure Law section 160.59.