Please help! Positive line disappearing in a minute

Hi ladies, my period was due today but nothing yet. I made an easy at home pregnancy test this morning. Second line appeared immediately and I showed it to my husband. We were so happy then the line disappeared in a minute! We were so confused and I run to the market to get a digital test. It said “not pregnant”. I cried an hour and took another easy at home pink strip test and we saw another line again (if I saw only myself I would say I’m going crazy) and it disappeared again!! What is going on? I am losing it!! (We have been trying for four months)