If you believe in a God who controls the big things, you have to believe in a God who controls the little things. It is we, of course, to whom things look 'little' or 'big'.
There is no problem too big or too small to share with God in prayer. What is troubling you today? Big or small – it doesn't matter, turn it over to God right now in prayer. Then, take comfort knowing that God hears all your prayers and answers them according to His perfect will.
Do not be anxious about anything, but in everything by prayer and supplication with thanksgiving let your requests be made known to God.