To check the status of your boosted show simply go to the show page you have selected to promote and you'll find the information there:
Please note that when you purchase an ad you are guaranteed a certain number of impressions (people who see it), not necessarily listens (people who click on 'Play').
The conversion from impressions to listens is more complex, anything from the title of the show, description, and tags, to the picture selected, could convince more people to click play. Make sure you give as many details as possible on each show, this will help increase your conversion rate.