Light periods ??

For the past two periods I’ve had now were really really light. I’ve cramped here and there but barely much bleeding ? This is out of the ordinary for me. I’ve been on a new birth control for a few months now ?? Could this be the cause or should I be concerned? I’ve always had heavy heavy periods ever since I got my period young. It’s never been this light before hint the concern. I have been stressed but I’m always stressed/anxious and I’m not too overweight for my age/height. Not sure what could be a big factor in it. I’ve taken pregnancy tests and all negative? I don’t feel sick or anything I don’t feel any different ? Thoughts?