One of the things that you should be looking at is Google Analytic's. I look at this frequently to see what is happening on my blogs. This gives me various views of how everything is going. I can look at daily stats, weekly or monthly and see if I am making progress.
I can also see where people are coming from on the planet, how long they are spending on the site, whether they are referrals, or organic referrals and more.
Go to Report
Go to Report
I can also look and see what percentages are for new versus returning visitors- ie am I still attracting new people.
78.57%New Visitor3,548 Visits
21.43%Returning Visitor968 Visits
Also with Google's New Social section you can see what social network is helping you progress or is a waste of time and no one I know has too much time to waste. Put your posts where they will be seen by your audience.
If you aren't yet using some type of analytic tools to see how your blog is doing you really should be.
If you use Twitter as I believe you should be also trying out http://www.socialbro.com/ There's some great information you can use here such as when is the best time to tweet based on your followers.
I'll assume that you also use Facebook and if you have a business page are you looking at your "insights"? You will be able to see a great deal about how you are doing, what your reach is,what the engagement level is and more which can help you in your posting.
I must admit that learning to use these analytic tools takes time but you need to be able to use every tool possible to evaluate how you are doing. Constant learning is a key component to using socialmedia to its best advantage and using analytic's can help.