IUD help!

Vanessa
Hello, this is my first post on here and I need some help or advice ! I'm 21 years old, I had my son pretty young (17) and about a year after I had him I got the Mirena IUD bc. I got it taken out in Jan this year because I kept getting yeast infections and my GYN suggested it might be because of the IUD so I had it in for a total of 3 years (a little over). I got my first period after that the 11th-17th (Jan) then again the 31st-5th (Jan/Feb) then again 29th-4th (Feb/March) then haven't gotten it again since then. I'm not trying to get pregnant but we're just so used to not having sex with condoms (me n my S/O) so we kinda had sex 3 times without a condom (I know I know I'm asking for trouble) but I did check if it was during my fertile window and according to the app it was far away from being fertile. I'm wondering if this may just be an irregular period or if anyone knows when it'll start to be regular after the removal? Cause the uncertainty/irregularity is frustrating!! Anyone with a similar story please help!