So I went home and google-d for tips to stretch shoes. Even went to the extend of going to Ikea to purchase the OMSORG shoe tree. I placed them in the flats for a good 24 hours before trying them again. Managed to stretch them by maybe a minute 2mm. Not good enough.
I was quite surprised that the internet offers hundreds of tips to stretch shoes. Some involve Ziploc bags, water and a freezer, others require stretching liquid. One caught my mind that doesn't involve stuffing your shoes in the freezer among your poultry and ice-cream *yucks*, so I decided to try - and lo and behold, it worked like a charm!
Here's what you need - a pair or two or really thick socks, a hairdryer and too-tight shoes. Put on the socks (make sure they're really thick) and then stuff your feet into the shoes. This will hurt but it will be worth it in the end!
Next, take the hairdryer and heat up the areas that are tight for 5 minutes while stretching and flexing your feet. Let them cool while keeping the shoes on.
When they're cool, remove the socks and check the fit of the shoes. Mine fit like a glove! Repeat the process if they're still tight. It's a tried and tested tip, but only if your shoes are 1/2 to 1 size smaller than your usual size.
I'm gonna do it again tonight to loosen it a bit more :)