Hello, lovely girls. I wanted to ask you, has anyone ever experienced …

Hello, lovely girls. I wanted to ask you, has anyone ever experienced something like this? My cycle is irregular and there's a delay of 5 days already. I took a test on day 3 of the delay with sensitivity of 25-30 ml. negative. Last time it was also like that, and only on the 8th-10th day of the delay showed a positive result. But then my cycle was 16 days... So, I don't even know what to do.