What Causes Mood Swings, Tiredness And Abdomen Cramps While On Contraceptive Pills?

hi doctor i am 25 and for the past 6 weeks been on the pill as i came off the implant but for the past 2 weeks i have been a lot more tired feeling weak and been having stomach cramps with light spotting and being or feeling like i need to vomit can you help as it is really getting to me i have been having a lot of mood swings aswell thank you so much samantha