Period mia

Alright so my last period was july 22-28th. According to this app last month it was 4 days early. My periods are irregular and i have been tracking them for a couple years and my cycles can ranger any where from 23 days to 46 days. At the end of my period last month i got a uti and was on antibiotics for 7 days. My boobs arent as sore as they normally are but i have acne like i normally do. I keep cramping but no sign of my period starting. I had sex this month on the 3rd, 14th and 21st. We use the pullout method which i know isnt a safe method. They gave me a pregnancy test at the drs office right after my period and i took one last week which were both negative.