Hi Erinnjoy,
As Highcharts API says, yAxis/xAxis can be an array of objects, so you can have as many axis as you want. Look at the demo below. Notice how the second series is connected to secondary xAxis and yAxis.
API Reference:
http://api.highcharts.com/highcharts/yAxis
Example:
http://jsfiddle.net/d_paul/r890aact/7/
Regards.