grant from Washington from a Sam Martin Sam Martin got my bank account information before I realize it was a scam Seattle, Washington

I was lead on my a phone call of a 206 number claiming that I was to recurve a.grant of 7,000 dollars and ask how I wanted to receive it so I proceeded with my account information and so he have me his name of Sam Martin an so he gave me a confirmation number of JV116 and that I will first need to send a western union of the amount of 300 to be sent to a third world country and he told me once I got there to give him a call and then he will give me the information as to where to send it but I stop right there and told him that it will be a couple of days so he said for me to just call him back and that once I send the money then the 7,000 would go into my account. I have thought about calling him and just lie to him just like he did to me and pretend that am at western union to send the money just to see what more information I can get. Please help cause now he have my bank account information and my name and address.