I Am 16 Years Old And Have Been On The

I am 16 years old and have been on the pill for 3 months now. My period came before i took the sugar pills and it started off light, its been 6 days and ive just started getting normal bleeding. Tonight i woke up with really bad cramps that felt like someone was ripping out my insides, i had a shower and a big jelly kind of thing covered in blood came out. Any idea on what this is? I have a photo if you want to see could you please email me. Thankyou