Six miler with pickups

Today was the first "hard" running I've done since the marathon. The plan was to warm up for a mile - then run hard for 3 minutes (around 8:00 pace) then recover 3 minutes - repeat 4 times. Each pickup ended up being around 7:30 easily. Im thinking I need to do a speed test and run a 5k or 10k to see where I stand in the speed world. Moved the final kick back to the light to middle gate ~ .33 miles.

Total Distance: 6.03 miles
Total Time: 53:28
Average Pace: 8:52
Average Heart Rate: 158 bpm
Max Heart Rate: 183 bpm
Average Speed: 6.8 mph
Max Speed: 9.7 mph

Splits (Time/Heart Rate)
9:38 / 136 bpm
8:10 / 161 bpm
8:42 / 163 bpm
8:46 / 162 bpm
9:10 / 162 bpm
8:43 / 167 bpm

Weather
Temperature: 61.7°F
Wind Speed: SE 8.1 mph