2 room apartment in Falun

As of April 14 I will have an empty apartment that will remain vacant until May 31. I was offered an apartment on February 3 which I accepted. I gave notice on my apartment immediately on February 3. But because the notice period is three full calendar months, this means my notice runs until May 31. And the move-in for my new apartment is on April 1... I completely missed this. I thought I would have the apartment until the end of April. But it turned into an extra month. I won't be able to afford paying two rents for two months, so I'm ...