cycles after myomectomy

Kristin
Hi! I'm looking to see if anyone has had similar situations to what I'm experiencing.
I had an open myomectomy on 9/15/15 and removed a large fibroid from inside my uterus. Before surgery my periods were pretty consistent with 27-28 day cycles. Now it seems my cycles are so much longer. Last month I had a 34 day cycle which didn't bother me but I have yet to see a period this month and I'm on CD 38. I waited the 8 weeks to have sex and always use a condom as we were advised to wait 6 months to ttc. I took a pregnancy test yesterday and it was negative. I have symptoms like my period is coming but nothing! The worst symptom are sore breasts and my nipples are larger and VERY sensitive.
So, my question-has anyone had weird or longer cycles after their myomectomy. Should I be concerned? I figure if it doesn't come by Monday I'll make an appointment. I'm going to test again with FMU because I didn't yesterday. 
I'm scared to be pregnant this early after surgery and also scared I'm not. We want a baby so bad, but we want to be safe.
Anyway, sorry this is so long and thanks for reading and hope for some input!