How can one deal with oneself and the feelings of guilt and psychological pressure after postponing the wedding, and is this considered a tribulation?

The delay of the wedding due to financial circumstances is a simple matter and should not cause all this thinking, worry, and pangs of conscience. The questioner has not wronged his wife. He should proceed with his affairs, seek Allah’s help, and take the necessary steps to consummate his marriage. He should not burden himself beyond his capacity or excessively blame himself for something that does not warrant blame.