Not sure if im late or missing my period

[Confusedmel]

So I downloaded more then one app.  Trying to track my cycle. One has been accurate for the past 4 months. I was going by 28 day cycle, I would be a day or two late. Well last month my cycle changed to 34 days; meanwhile, I though I was 6 days late.
Now this month, due to all the different app. I'm not sure what my cycle is doing this month but i'm basing it on the last cycle, that was 34 days long, I'm now 3 days late and 18dpo. I don't want to run and take a test and either waste money or get a false negative. I have no signs of being pregnant just signs of my period coming. Back pain (my boyfriend says my back looks a little swollen), bloated, and a little fatigue. should I bother worrying or is af playing games with me?

[Ezkh80]

Hi there. Good luck with your ultra sound. Ill be interested to hear how you go. I'm also going to see my gyno as neatly 10 days late and negative tests - hcg 2...

[Confusedmel]

Just an update, I got my back my blood test results: and I am not pregnant. Still no af I'm now 17 days late; guess I just missed the month of feb. My ultrasound may tell me why I have been having pelvic pains because that was different.  Anyway, thanks everyone for the support and advice during these frustrating  weeks. :) God bless.

[Confusedmel]

Negative test. This is annoying why won't af just come already.

[Confusedmel]

Thanks heather I am going to take a test today. I just hope and pray I get an accurate answer.

[Heather5]

Do you know for sure that you ovulated 18 days ago? If so, I would definitely take a pregnancy test. If you go more than 18 days without getting your period, you're most probably pregnant!