My Last Period Was Aug 23rd And From My 3rd.of

My last period was Aug 23rd and from my 3rd.of the period I have taken gonadotropin injections. On my 14th day I had 3 dominant follicles 21mm, 20mm & 18mm and I was given hcg 5000ui shot on that day. On my 17th day I went for scanning again and doctor told me that I have.ovulated. she said I. Might have ovulated on my 15th day as it takes 36hrs for ovum to release. I have not got my periods till today. When can I test?