North Lakes parkrun 2nd 17;29

I warmed up by running the 2.5km from home to the start and did 3 strides. The start is slightly downhill and there is a major width restriction on the pathway due to road works (it narrows to about 1m !). So I wanted to get out fast to avoid being blocked. Everything appeared OK till close to the end of the short grass section as I nearly over rotated and came close to tumbling over (like I infamously did at my kids sports-day Parents race back in 2004 - see if I can dig out the photo of that hamstring tear) anyhow to prevent myself from falling I splayed my right leg to break the rotation and thereby strained it! Immediately it was painful and I battled mentally should I drop out ? I continued on, taking a brief lead before a youngster breezed up on my shoulder and overtook me at 1KM and gapped me soundly. 
Although it was painful I was running OK so I continued through the first lap in about 5;30 and the second lap in about 11;39. That second lap had taken far longer than it should have and I realized my time wouldn't be great. The third lap requires lapping people the whole way but the serious road works width restriction only presented minor inconvenience. My official time was 17;29 for second place (first over the line was Jai Hockey in about 17;15). I hobbled back home for 10.4km for the day. I rested Sunday and Monday to give the hammy some time to repair.
Will see how I go beyond that before recommencing.
Interestingly, I wore my heart rate monitor and  got the HR up to ave 160 and a max of 170 during the 5km parkrun section.

Did this hamstring tear from 2004 lead to my current chronically sore hamstring?