Can periods change over time?

My periods have changed over time they used to last 5 days averagely since I was 12 but now at 23 in the last 2-3 years I've had spotting for 3 days as a period and havnt worn pads/ anything for 3 years. Now I havnt had anything for 9 months now I suddenly have spitting again. Was on contraception for a few years now I havnt been on any at all this year I wanted my periods to return to normal but they havnt so can your periods actually change or could there be something going on?