I have been wondering about this for ages

[NotABanana]

If you kept having a monthly bleed and therefore didn't know if you were late, or by how much, when would you do a pg test that would give you the right result?

I don't really understand the question...
Are you asking how, if your "periods" continued you would know to take a pregnancy test?

What if other things made you feel like you were pg but you still had bleeds. How would you know when to test?

Well I guess if you feel pregnant, then you ought to have enough HCG in your body for a test to show positive.

A few months ago I got what I thought was my period but shortly afterwards realised I might be pregnant and did a test (which was positive, but the preg turned out to be ectopic). I did the test because:

1. I "felt" pregnant - nothing I can really put my finger on, I just did; and

1. I chart my temp which was higher than it would have been had something not been going on.

Just as well I did; it may have saved my life .