Over the weekend I did my first BIAB, lots to learn and room for improvement

Anyway. I had the bag 'tied' closed rather than open around the pot, i think this is the primary reason for the poor efficiency. The OG came in at approx 1.041 rather than 1.063 discussed. So a quick google found a calculator which suggested I add in 1kg of brewing sugar to compensate for the poor efficiency. Which I did, by taking out some of the contents of the fermenting bin, added sugar, a little heat and then cool, back to the FV. (sunday morning)
By Sunday evening, some foam appearing but no bubbles in the airlock.
Today, no foam and a gravity reading of 0.0024. A quick taste, it seems quite sweet, with some bitterness (that'll be the hops then) I am still learning a lot and need to dedicate some time to 'off flavours' but i didn't detect anything off - it tasted better than the kit's i've been brewing!
The original bag of grains was tipped into the composter Sunday evening, so i can't re-mash with the old stuff, it'd have to be fresh grains.
Any advice would be greatly appreciated.
cheers.
JT