Which day should I expect my period?

Sorry this is kind of long! Hubby and I are TTC. This month (June) my period was suppose to be due Friday the 24th. On Tuesday the 21st I had a very light bleed. More than spotting but definitely not like a normal period flow. It continued until early afternoon Wednesday the 22nd then stopped completely. My cycles are normally 31 days and period lasts 4/5 days so that was really unusual. No bleeding or spotting the rest of Wednesday, all of Thursday or Friday. Saturday the 25th I had a couple dots of blood when I woke up and that was it. I took a test on Tuesday morning the 28th and it came up negative. Could that bleeding have been implantaion? Or could that have been considered and early period? I'm gonna wait a week and test again but otherwise I'm going to wait and see what happens with my period in July. This app says I'm due July 22nd but Ovia says I'm due the 19th. All the info is exactly the same put into both. Which one do I go by? Lol