Mommies on Friday I went to get my deppo and when I was out the shower on Saturday I feel like a big…

Mommies on Friday I went to get my deppo and when I was out the shower on Saturday I feel like a big ball inside my arm .-. I still feeling it but a little smaller... should I go back to the doctor? Or it’s just a reaction?? I don’t want to get pregnant yet!! 😫 and it’s actually scared me to have that little ball there