My FSH is higher than yours and my AFC is lower, but this also happens to me. In fact it's happened in all but one cycle where I took EE. Like you my E2 is usually higher on CD2/3. I'm actually in the middle of a TI cycle taking EE and my E2 has been below 20 for almost 3 weeks. But, in all of my EE cycles, my E2 eventually started to rise and I developed a follicle and ovulated, and it usually happens quickly- like once it starts to rise it takes off. So we've learned that I need close monitoring on these cycles.
I've never done IVF on it so not sure if there's a difference here, but they've always told me they'd give me 4 weeks and if my E2 didn't rise they'd give me provera to bring on a bleed and start over.
I'm not sure why this happens. For me, because my FSH has been really high, I've thought that it wasn't that I was over-suppressed by the EE per say, but that it takes a while for my body to get used to the lower FSH level before it can respond if that makes sense.