Advice?

Hi, I’m 31 years old and TTC for baby #3. I have a 10 and 8 year old from a past relationship and just got married. Back in September I had the Paragard IUD removed and haven’t used protection since. I’ve only been tracking my period on this app since August. According to the app I am 4 days late, I’ve taken multiple hpt and all are negative. I have some mild cramping and slightly tender breasts but nothing crazy at all. I also had gastric bypass surgery in 2009. I don’t know what to think about this, anyone have any suggestions?