losing hope....

Stacey • Wife. TTC baby #1 since March 2012. Ivf cycle #1 August 25th 2017(failed). IVF cycle #2 January 2018 (3 frosties). FET March 2018. BFP 3/27/18. Due 12/03/18 born 11/30/18. Natural pregnancy #2 SURPRISE! BFP 10/26/2020.
A bit of background on me: been off birth control for 5 years and nothing. 3 rounds of clomid, 1 month break, HSG test good, hubbys test good, no real answers as to why? 
This month I'm on letrozole to avoid side effects I had with clomid. I was spotting for a week before my period would come was the most concerning as well as all these pregnancy symptoms that would get my hopes up just to be let down again and again. 
I'm cycle day 25 today and been nauseous to the point of throwing up twice, mostly in the morning. But I started spotting again Tuesday when I'm not due for af till at least Sunday. BFN this morning as well.... 
I just feel like there's no way I'm ever gonna get pregnant at this point. Anyone else have spotting up to a week before your af was due and still get a BFP?! It's not super light or heavy this time it's red but with clomid it was brown. Lasts 5-7 days then af comes in full force.