Ovulation and due date help!

I’ve had a positive test but I’m struggling to understand the timings, they just don’t make sense to me. 

- I have irregular cycles usually 32-40 days. 

-I had an LH surge on 22nd May. 

- I had a normal period on 2nd June until 7th June (that was a 31 day cycle). 

-7th June I had my Copper IUD removed. 

- On the 14th June I started having pregnancy symptoms and faint lines on tests. 

-15th and 16th had constant pelvic pain into my lower back, almost definitely implantation pain (no bleeding). 

-16th positive test. 

I’m having nausea, swollen boobs, bloating, irritability. 

But I just can’t figure out how many weeks pregnant I am given that I had my normal period. Did I get pregnant on my period or just after? I don’t see how given my cycles are usually long (never below 31 days). 

Worried I might have something wrong with me. 

Thank you for helping 😊 xxx