I had the Nexplanon contraceptive implant in my arm in October 2011. I didn't have a period at all for 3 months, then I got one 2 weeks ago, on the 7th of January. It lasted for about 7 days, and then bleeding stopped for about 2-3 days.. But today, I've started to bleed again, and it seems like it's going to be another period, only 2 days after the last one. What could have caused it? I don't understand why I've gone from not having a period for 3 months to having 2 in one month. Will it continue to happen? 2 in one month..?