I'm sorry
@DuncanLord but 3.2/3.3 is a hypo in anybody's book, I don't care what your hospital app says. DAFNE suggests 3.5 and below because non diabetic people can drop that low, but for those of us on insulin we need to preserve our hypo awareness so whilst a 3.5 may not cause us any harm, it can erode our hypo awareness and we need that to detect when our levels are dropping dangerously low, so we actually need better hypo awareness than Joe Public because Joe public isn't likely to go below 3.5 and risk brain damage/unconsciousness.
Hypos should be treated with 15g of fast acting carbs (dextrose tablets or jelly babies, orange juice, full sugar coke) not a biscuit (I think
@Kaylz had a typo in her post and it should read "wouldn't" not "would") which is slower acting by comparison. You should then be checking that levels have come up above 4 15 mins after treatment and if they haven't come up, then another 15g fast acting carbs should be eaten and the hypo treatment is best chewed thoroughly as absorption of glucose starts to occur in the mouth and can transfer to the blood stream quite quickly through the cells in the cheek walls.
These are basic rules which it is important to follow because hypos can often affect your ability to think straight, so it is important to develop a routine or habit for treating them early on so that it becomes automatic in case your levels drop faster next time and a biscuit is too slow to bring you back up. Dropping from 7.4 to 3.2 in an hour and a half isn't actually all that fast. I used to drop from 15 to 5 almost every morning in about an hour until I realised I needed to bolus over an hour in advance of eating breakfast and I have certainly dropped into hypos many times when I thought my levels were steady and safe.
I accept it worked fine this time but please have a rethink about your hypo treatment and use something faster acting and 15g is the recommended amount which is 3-4 glucose tablets or jelly babies and always have your hypo treatment to hand and always retest to make sure it has worked. Developing these good working practices in the early days of your diabetes journey are important and particularly when your job and the safety of others relies upon it.