Super light spotting at the start of my period this month??

So I got my period yesterday, but it's super light spotting at best? Like I feel like I'm wasting pads because it's so light I'm not getting any blood on them. The last few months my periods have been super heavy and painful (they haven't been like that since I started birth control, but they've been steadily getting worse) so this is throwing me off? Is there possibly something wrong?