PPL - Solo Navex EGKR (Redhill) to EGKR (Redhill) via Maypole

This was an hour building Solo NAVEX from Redhill (EGKR) to Redhill (EGKR) flying locally to the East over Maypole.

Key issues and points for learning:
1) 1:14:30 Allowed altitude to descend briefly below 1200ft before joining Downwind
2) 1:16:30 Final approach - lined up for wrong runway 08R instead of 08L
3) 1:18:04 Taxi back after leaving runway (didn't understand instruction from ATC, needed reminder).

This resulted in an unhappy phonecall from the ATC operator to my CFI who then decided to cancel my upcoming test quoting "More work req". On me asking what that means, he said "You need work on situational awareness".
My next question was, so how do we work on that, the answer given was "We fly out to locations on the map which you have to plan and navigate".

My concern is that this video proves I planned and navigated to Maypole and back more or less without issue. The issue was approaching to the wrong runway (second time in the same week) at my home circuit. The other issue was dropping altitude briefly prior to Downwind.

My eyesight is fine, but I did not even see 08L from base. I simply one runway 08R and lined up with it.

Any suggestions for improving are welcome.