I had much tighter curls when I was younger that have since developed into 2c/3a/occasional 3b. It's not unusual for your curl type to change and most curlies note that their hair is filled with variety of curls and whirls. It is possible for your hair to change into 3a or many different types over the course of your life.

The environment you live in can also have an effect on your curl type and their formation.
Type -3a/3b
Products- Herbal Essences TT Mousse