It was likely the felony you mentioned that resulted in you being sent home. Also, something to remember, if you are a probationary employee anything the agency deems ‘unfavorable’ can result in termination of your employment. And typically, as a probationary employee you have no appeal rights.
You may want to consider consulting with an attorney in the state you received the felony in. Perhaps, if the law allows, you can have the arrest and/or conviction expunged.