Firstly, you need to ask yourself if you can get through the phrase without passing out. Can you sing from the start of the sentence to the comma without pressing on your belly or squeezing the last drop out of the note?
If you can – then you are on track.
If you can’t – then think about reducing the amount of air in your tone.
Secondly, you can check by putting your hand in from of your mouth (about 3cm away from your lips). If you feel a lot of hot air you have a lot of air in your tone. If you have just a slight whisper you have less.