Am I pregnant?

Since January I have been having lots of positive pregnancy tests and also a few negatives too! I even had one clear blue tell me I was 2-3 weeks and the following week I took another one and It said 'not pregnant' the two tests below were taken within the same week; one positive and one negative. I've been to the doctor and the test I took there was negative, this is really confusing me! They've referred me to have a scan which I'm having in the morning at 8:45, what does everyone think? Anyone else had this at all? ​