Slightly different circumstances but a partly retained placenta (unknown) that fortunately passed naturally without infections had been causing me some very odd symptoms whilst in situ in the cervix. I spent 2 days being kept in as they had no idea what was causing my light headedness, dizziness, faint feeling, nausea and high blood pressure. As soon as it moved they realised what the cause was and said the cervix nerves can cause such issues. Coil change I would imagine messes with the nerves sometimes.