***What to do next...ttc for 11 months

So we’ve been ttc for 11 months and ever since month 4 I’ve been seeing my gynecologist and I’ve taken 5 cycles of Letrozole. It seems that every other cycle on letrolzole I’ll get my period so I ovulated? and then the next I won’t so assuming I didn’t ovulate. Since we’re close to a year I’m tired of taking this and nothing happening my hopes climb and then go away. I’ve had vaginal ultrasounds for the first 2 cycles before I would ovulate and cycle before this one I was positive for ovulation but this cycle I’m almost two weeks late with a negative.

What should I do next? See a specialist? What does that entail? Has anyone else had this problem with Letrozole-where every other cycle you get your period then miss it and have to take provera?

Any advice helps!!