Pads ?

my mum bought me some stay free ultra thin pads and thier like so comfy but do they leak? im going to bed soon [it 10.11 pm here] and im afriad theyl leak cause they have a plastic sorta sheet ontop and the ones i used yesterday [libra] didnt they had cotton on the part that touches you so im sorta worried theyll leak have you used them before ?did yours leak wat pad brand do use? i got my first period yesterday