Hello ma'am and welcome.
Clots can be seen and associated with a number of conditions but is also considered normal if seen in women who use tampons. What happens is that when a tampon is left inside the vagina for long (which should strictly be avoided as it can result in infections), they blood that should otherwise get soaked up in the tampon can also stagnate and forms clots (which is natural for stagnant blood). But this cannot be assuned in your case. It is best to visit a doctor and request for a bimanual examination along with an ultrasound
examination to ensure good health.
Hope this helps.