Nyone experience this before??

Ladies need some advice I'm exclusively breastfeeding my 4 and a half month old son I had him December 23rd I had my first. In February and again in March never had it for April and have yet to have it for may I took a pregnancy test on Friday and got a faint positive throughout the weekend I retested and had negatives or they could have been very very faint positive today I tested with first morning urine on an 88-cent cheapie and got another faint positive First Response in all of the other ones have been negative but how common is it for false positives has anyone experienced this before