Quick LH Surge!?

Hello,

This is my first cycle with letrozole and I was prescribed 2.5 mg. I took the full dose which was for five days and caught my LH surge, my husband and I ended up BD on the same day of my peak and two days before my peak, but is it normal for the LH surge to only last a few hours? I’m already back down to the baseline level for the LH levels. 

**I don’t normally ovulate regularly so this is all pretty new to me on our TTC journey