not sure what’s going on!

i’m almost a year postpartum and i’m on the depo shot, well once a month i was throwing up roughly around the time i had my daughter but the went away a couple of months ago. Now i have been experiencing lots of nausea when i eat or drink and severe cramping almost everyday, i had some spotting about 2 weeks ago but we are not wanting or trying to have another baby right now. i need some help to figure out if its possibly hormones trying to balance or something else!