confused...

My last period was 10.31.2015 I haven't had a period since then but on 12.15.2015 I was bleeding light for 3 days only and my periods are normal I went sledding today with my so and family after we got home I went to the bathroom and wiped to see very light pink? any one have this before or what it could possibly mean? me n my so have been trying for a year now