Thanks for the query.
The possible causes for your problem are :
- Blood loss during the delivery can cause anemia and that can present with palpitations, dizziness
- Side effects of the depo.
. Some women may have postpartum depression after delivery.
So you once consult gynecologist, get examined.
If anemia is there, you need iron supplements
If the cause is found to be depo, you can shift to some other contraceptive
In case of postpartum depression, you may need psychological councilling and support of your family members in dealing with the problems.
Check for thyroid profile once.