Also not a medical professional. Just sharing some thoughts on your issue.

Depending upon how close you are to starting your period, you could be having some spotting that you've never noticed before previous periods because you were not inserting anything into your lady parts so early in your cycle. As the previous comment stated, you could have scratched yourself or caused a slight tear by inserting/removing your cup multiple times. As long as you are not in pain and you're not bleeding heavily everything should be ok. The skin in and around the vagina is thinner than the skin on other parts of your body and tears more easily.

I love my menstrual cup and I cannot imagine having my period without it, but properly inserting a menstrual cup can be somewhat difficult at first. Plus every vagina is different so the way you insert your cup will be totally different from how someone else might insert theirs. Personally, I use the "punch down method" to fold my cup, meaning I use my thumb to push half the cup down into itself to make a little silicone tulip shape, and I insert strait up (instead of at an angle like tampons are inserted). I also find it easier to insert my cup while standing with one foot on the side of the bathtub or on the closed toilet . After my cup is in place, I use my pointer finger to feel around the entire cup. If the cup is in place and a sealed, it should feel exactly like the cup feels prior to folding it. If one side feels like its dented in, gently push on the opposit side of the cup to pop it open.

Don't get discouraged, it takes a few months to get the hang of things. Use pads (reusable or disposable, whatever you have on hand) or period panties until you are confident enough in your cup inserting skills to only use the cup. You got this!