I didnt have any problems for 3 years. But I did start to have pregnancy symptoms: headaches, morning sickness, loss of energy, you know that stuff! Well I was not pregnant just some side effects from being on the shot. It had tricked my body into truely thinking it was pregnant. So I had to stop. I loved it while I was on it. I have migrains anyway so that never came into consideration. They were not more or less with the depo shot. It's hard to say how long it takes to completly get out of your system it takes some longer and some its within the first month. Just give it a couple months on the new one and see how it goes. If you are still having the migrains go talk to your dr again. Just hang in there! I know it sucks! What are you taking for the migrains?