Can pawn attack queen?

I'm a beginner and am learning to play on chess.com's iPad app. I'm white and have pawns at f2,f3 and h3. The computer just played it's black queen to g3 but now it's my turn and for some reason the app won't let me attack the queen with my f2 pawn. Why?

is your king behind the pawn that you would like to capture queen with? u cant make a move that puts your king in check. thats my guess

 Yes, if there is a black Bishop pinning the pawn to your King, you will not be able to capture the Queen. If you showed us the board position, that would help to answer your question.

Just happened to me two of my pion could take the other queen and the game would not lets me get it ... I would not be chess or what ever wierd I'm new to the game around 800 elo