Hi my period is irregular and my last 1 was on June 29.
But I have been sexually active since then I was on birth control but missed a few n we use the withdrawal method.And a couple of days ago I had some on and off spotting.
I don't have any symptoms of pregnancy except for missed period
I saw my doctor and she said that my cervix didn't look pregnant and that it
Wasn't blue.
She also said that getting blood work done wasn't needed what do you think?
And today I'm having some cramping.

You could be about to start your period based on cramping and spotting. I tend to agree with your doctor. If another week goes by without starting, then contact her again.

Without having regular periods, its hard to predict if you could be pregnant or not but since your doctor did a physical exam, that's the best information you have to go on.