weird, clumpy discharge???

so recently i’ve noticed that my discharge has been, like.....clumpy? i’ve always had a lot of discharge (if someone could explain that too that would be great), but now whenever i use the bathroom i see like clumps of it on my panties. it’s nasty and i don’t know what’s happening. i’m not sexually active, so i doubt its an std, but if you have any information or theories PLEASE let me know !! because it’s honestly freaking me out.

(also i’m 15, idk if that helps at all)