Mail keeps stuck in Drafts box - Exchange 2013

i,

This is my first time setting up a Exchange server, but i'm stuck at sending mail. I am able to receive mail, but my send mail keeps stuck in the Drafts folder.

I'm using a smart host, provided by my provider through port 587, since port 25 is blocked. I have a feeling that my problem is somewhere in DNS, i already did a lot of reading but i can't figure out the problem.

My dns settings are:

where 192.168.1.22 is my Active directory controller with DNS.

Are there any changes or things I need to add to my DNS controller?

Thanks in advance!