What's going on with my cycle?

So today I am 35 days since my last cycle. 
My last period was Monday 2nd of November.
The last time I had sex was October 17th (my hubby is away for work 2 months on 1 month off), but then I thought I had my period on the 2nd of November. 
Took a test this morning even though I hadn't had sex since October, and it came back negative.
I am usually 28-29 day cycles religiously. I track my period etc on an app, and it basically told me this morning I can't track you anymore till something happens down there... Lol! 
I did have an ectopic pregnancy back in May, but have had regular periods since July. 
My boobs are extremely tender as well.
I have recently put a little more weight on my body and not sure if that has messed up my cycles...
Anyone got any insight into what is going on or any suggestions on what I should do...
We are trying to conceive as well....