High estrogen levels ?? IUI cancelled ? HELP!

Looking for some insight last cycle I did leterzole CD 4-8 but unfortunately couldn’t do my iui because my partner was out of town got called last minute for work however we was able to do timed intercourse ( went in cycle day 12 had two mature follicles both measuring 20’mm) no trigger but it failed. I was supposed to do iui this cycle went in today for day 4 bloodwork , was told my estrogen levels are high meaning my body already started to produce a follicle and my doctor wants to cancel my iui cycle. I’m so upset has this happen to anyone? Like wouldn’t I be able to just move on with a natural iui cycle ? ( I ovulate on my own btw) just so upset 😔😔