What does low estrogen level feel like?

I have been on the same dosage of EV IM for a few years (3.4mg every 3.5 days). I had SRS three months ago. I then stayed with the same routine and did a lab work that showed my level at trough is the same as pre SRS (300ish pg/ml).

In the most recent injection, I did 3.2mg instead of my 3.4mg. Now 12 hours before my next injection, I started feeling more tired and sleepy than normal but it could also be I only slept for 5 hours last night.

I have two questions: 1. What are the symptoms of estrogen level being too low among trans women? 2. Is my 300ish pg/ml level at trough too high?