question

One of period calendar says in 2 days late glow says I’m one day late I had a period oct 1-5 and now it says I’m suppose to have another one oct 26 for one app and glow says oct 27 how can I have two periods in one month I have been having sex With my boyfriend but I’m not sure if he cum inside because he pulled out for the most part I have no signs of my period or being pregnant but my original period calendar says I’m two days late glow says one day late I’ve had an oct period so when should I take a pregnancy test because this is weird.