Help implantation or not

Ok so last Monday I had a positive pregnancy test but the lines were light so I didn’t want be all happy about well Friday I tried doing a second pregnancy test it came negative Saturday I did my third pregnancy test negative as well so by 12pm I went to the restroom boom I saw light red blood just to clean with paper toilet later on my pad wasn’t wet with blood I’m a heavy period gurl just because I’m irregular well I didn’t bleed no more I’m having bloating breast are sore cramps are severe and having back pain as well can it be implantation bleeding or period I took off my nexplanon feb 15 and didn’t get a period I’m so confused I need advice