With encouragement from others on here, I decided to re-do W7 and consolidate the non-stop 25min run until I feel comfortable with it before moving onto W8. So this morning I did the 25min run for the fifth time in two weeks and am now happy to say that I can definitely feel huge improvement upon each run.
The main difference between the first 3 runs and the last 2 is that I stopped going to the gym to do my weights on the "rest" days between runs. I thought lifting a few dumbbells would help to supplement the runs but it's become apparent that it is actually more taxing on my body than I realised. Not that I've stopped gymming, I physically feel so much stronger during my runs, like I have an increasing amount of fuel left in the tank to keep going at the end of the last 2 runs. This positively affects my runs mentally too. I managed to relax and go with the flow with more ease. On the first run I couldn't wait for Laura to tell me to stop but today I completely forgot the clock and ran at full sprinting speed for the last 3mins today and still feel like I could have kept going for more.
I think I am ready for Week 8 now