Help ! Worried periods have always been 5 days long last two cycles last 3 days only !

scotland lass

Im not sure if the change is age related or not . My Af has went from 5 days like clock work to 3 days for last two cycles? They are arriving on time every month. And am still getting a positive clearblue ov test every month. I had a miscarriage back on oct 2018 .worried shorter cycle means menapause is around corner 😑😑😑