I filed my taxes & indicated that my state tax that's due should be deducted from my bank account. However, it appears that I still need to send a check. How do I check ?

When you filed your state return, you would have been presented options to pay by direct debit and if you chose that option, you could also choose the date the payment should be withdrawn. Check the worksheets and instructions in your saved file for this information. 

See this help article for contact information for the different state tax agencies. They have options to contact them or look up the status of your payment or to make payments online.