Could I be pregnant?!

Danielle • 22 yrs old☉ Mama to a rainbow baby due August 4th, 2018🌈 Expecting my 1st baby❤

so I had a miscarriage that started on Sept. 7th and ended on Sept. 11th. we started trying again right after I stopped bleeding as the doctor said it was okay. I am on cycle day 26 and have no clue of when I ovulated because I am irregular. According to the app I am 4 dpo. I have been having nausea, achy, and bad headaches since Saturday 9/30. It kinda feels like i am getting sick with a cold. Could it be possible to get these symptoms this early dpo or do you think I just ovulated early?? I like never get nauseas... Very hopeful for this month as I saw a rainbow on the lake the other day only for like 5 mins! maybe a sign?? I hear you are very fertile after a miscarriage! please help!