I am 43 years old .I had my period on 19 April it ended on 21 st .I have a 21 day cycle .I has unoritected sex on 8th May .On 10th may I had a slight bleed that only last 18 hours .2 weeks later I took a pregnancy test and was positive .I have done a number of clear blue hpt 3 was positive and 5 have been negative,I haven't had a proper period since April.I do have a few sympyoms i.e. peeing more mood swings abdominal pains tiredness and montgomery lumps around my breast nipples bit tender but no pain. I have had some nausea but not much .could I be pregnant.I saw my obgyn end April and everything was good.

You almost never get a false positive pregnancy test, so yes you are pregnant, it is possible to get a few negative ones esp if you are not using the first urine of the morning,

Time to see your doctor to confirm, Then on to planning for the baby, names, beds and so on.