I agree with Joy. Your body is getting back to normal and sometimes during that process things get out of whack. It took me 2 months after both of my mc's to get back on track, And your body has gone under alot of stress due to the surgery. Im sorry for your loss.
It can take about 6 weeks after a miscarriage to get your period again. Because you had a surgical procedure to remove the tube and your sweet baby it might take a little longer than 6 weeks. After my natural miscarriages (non-ectopic) it took 8 weeks for me to get that first period each time. So everyone is different. Don't stress about it or think about it; it'll take time.