Hey Kathryn pretty well! Sounds like you are making good progress! Depending on the footing and terrain, your pace was either really good or respectable but no way was it slow! Keep it up!
I ran a 21+-mile trail race last weekend – SUPER HOT (it was an evening race and 93 degrees at the start) and ran 3:56 good for 10th overall. I hadn’t “trained up” for it though had done some 5-8 mile-runs and a couple 10 milers in the 4 weeks leading up to it.
Yes slow and steady! AND PATIENT! KEEP IT UP!