Hi Tamirra, sorry to hear of your daughter's plight. Has she ever had a smear test before or had this bleeding after sex investigated? (I realise she is probably under the age of Government recommendations for smears)
It could be nothing, but you've said she has been sexually active from an early age, so if she wasn't using condoms, then she may have caught an infection at some point, causing inflammation.
It could also be the coil, some women do experience irregular bleeding and abdominal pain with this device. It must be a worry and she sould probably see her GP as an emergency and not wait for an appointment.
I hope the news is good and the outcome is positive.