Sensitivity in teeth & gum line. Help.

I got scaling done 1 month ago. Before that I used to brush with a wrong technique without brushing gum-lines. After scaling I started brushing in the right manner covering the gum line, inside of incisors properly and inside of the molars by doing circular motions followed by swiping. In this same period of 1 month after scaling I have been getting too much of sensitivity in my teeth and near gum lines. Can you please help me understand why it is happening and how I can get rid of it. I am really scared as I have never had sensitivity before the scaling (1st time) in my entire life. And since I changed my brushing technique right after scaling as mentioned above, it's difficult to correlate and identify the reason for all this sensitivity. Please please help.