As you indicate that your food habits were poor as a vegetarian, you may want to consider the possibility that your symptoms are related to a vitamin deficiency.. iron, b12, zinc?? You would need to get a blood test to confirm whether that is the case and if so, whether there is more than one deficiency.
A multi does not have the amount of b12 that is required by a vegan.. so hopefully you are supplementing with the higher dose (ie. about 1200mcg/week). Many vegetarians have limited stores of b12 (unlike ominvores), so switching to vegan and failing to take a b12 supplement can quickly deplete any stores.
Do not supplement iron if you are not deficient .. there are serious health repercussions if you overdose. So make sure you check with a doctor before supplementing. Foods high in iron are soy, beans, and green leafy vegetables. But to ensure absorption of iron, you need have some vitamin C at the same time. Also coffee and tea inhibit absorption.. so if you drink them, I'd limit it to the a.m.
You need vitamin D in order to absorb zinc... Scotland is pretty dreary in the winter (like Vancouver!), so I highly recommend a D supplement. I also take a zinc supplement now and then as recommended by Jack Norris