As missionaries or preachers we also have to make sure, that we are an example in how hard we are working. Reality is that you have the status of a self-employed. That means that nobody will keep you in check. You have to realize that people are watching you and it is a very good habit to start writing down what you are doing the whole day. 

It is our job to lead people to the Lord Jesus Christ and disciple them. That is what our Lord and Saviour did and this is our main job. Focus on that and you will not have the time to worry about other ministries.