Possibly pregnant if so when should I test?

I have a very abnormal period even with my app that I’ve downloaded it’s hard to keep track. For example in December it said I had a 31 day cycle with my fertile window being between the 26th and the 1st of January. My period started on the 11th of January so I went and logged my period when I did that it changed my cycle in December to a 26 day cycle with my fertile window being between the 22nd and the 27th of December. This month it says I have a 33 day cycle my period ended on the 14th and it says my fertile window was between the 22nd and today. However I’m having some symptoms of pregnancy and wonder when’s a good time to test and if it’s possibke I got pregnant before my fertile window. I have some breast tenderness, I’m extremely tired regardless of how much sleep I get, I wake up with terrible heartburn, I’m having more frequency urination and some smells are way stronger then normal. Is it possible to get pregnant before your fertile window and if so when should I test without it being to soon?