What is this

Hi, so I had sex before the lockdown in March and I’ve been getting my period but please remember before you all say well then you can’t be pregnant that 30% of women still get a period and my periods are usually always 4/5 days and recently they have been 1/2 days 3 has been the longest and I’ve been getting so many pregnancy symptoms so I took at test and this was the result

But I got negative tests after.

What do you think it is?