If the baby does not accept the bottle as usually happens when weaning, you may try a feeding cup. Inserting a coil can trigger a cycle if it is medicated and I hope you had it done after excluding pregnancy
. Any medication gets excreted into the breast milk and does not necessarily alter the taste. It is more likely that the baby is ready to wean. Also, you can try feeding with a nipple shield for some time before trying to bottle feed the baby. Hope you find this information useful. Good luck.