newbie...going crazy

[doobydo]

Hi, I'm new here and desperately hoping somebody may be able to make sense of my situation. My LMP started on 23rd June. I have long cycles but generally ovulate around day 28 and get AF 12 days later. So, I ovulated around 21st July. During the first week August I started getting light period like cramps and a strange pulling feeling behind my bellybutton. Something in my head told me it was implantation cramping..I was certain of it. I took my first hpt around the 4th August but it was negative. Since then I have had no period. I have been experiencing symptoms of pregnancy since...my breasts are growing, they hurt, my nipples have changed colour and I have dark veins through my areolas. My cervix has risen and I have a lot of vaginal discharge. I often feel sick, tired and emotional. My skin is really greasy which I have never had before. The thing is I have been testing twice a week since the beginning of August and was repeatedly getting negatives until this week. On Monday I tested late afternoon and got a very faint positive. I tested again tuesday morning but it was negative. On tuesday afternoon I got another faint positive. Negative again on wednesday morning, positive in the afternoon and the same pattern today. I am so confused. I feel very pregnant but I don't understand these results. I think I am only getting positives on the late afternoons because I drink so little at work after lunch so my urine must be very concentrated. Surely I should be getting stronger lines by now. I have a dr appointment next week but just wondered if anybody had any thoughts in the meantime. It's driving me insane. Thanks for any help and sorry for the long post x