I Have Been On The Contraception Nexplanon Implant Since March

i have been on the contraception nexplanon implant since march 2018 my periods were fine up untill 2 weeks ago i was bleeding really heavy bright red and dripping from me and its still the same right now theres no sign of it going away or lighten up it had bits of clots in it and last saturday i have sharp shooting pains on the belly coming and going in waves