chemical pregnancy or inaccurate positive.

Firstly, any views or comments on this post would be greatly appreciated.

I have an irregular cycle varying from 34-50 days. I am currerntly on day 40.

I have been trying for 3 years and suffered a miscariage last may at 6 weeks.

This month i decided i wasnt going to monitor ovulation as i was quite frankly tired of it and needed a break.

Out of curiousity on Tuesday I carried out a pregnancy test and got a vvvv faint line. this line was so faint that i though it was an evap line or my eyes playing up.

I bought a predictor pregnancy test Thursday afternoon and within 5 minutes a faint line appeared which gradually darkened and is still showing on the test now.

Yesterday i bought a further predictor test and carried it out on the afternoon. again i got a positive result but it was fainter than the first test.

So today i carry out another predictor test thinking the line should be way darker by now plus first morning urine and too may disappointment i got a negative or an extrememly faint positive. i have done a one step test and that is negative.

The predictor test advise they test at 15 miu and the one step test i used on tuesday was 20 miu.

I hve a few questions i hope some one can give an opinion on:

1, if the one step test was lower miu wouldnt it of given a positive result the same as the predictor test.

2, why did i have positive and now getting negatives. I could understand getting 1 positive but two get two means strange.

3, chemical pregnany? does this sound like one?

My symtoms are:

sore breasts for 6 days now and slight cramping. i have had no bleeding a all.

thanks