Calorie count at a glance:
Breakfast:
Porridge Oats (how many grams? Made with what? Full fat milk, semi-skim milk, skim milk, water? All makes a difference!) = approx 150 - 350 calories depending on what you make it with
2 x slices wholemeal toast + spread = approx 110cals per slice = 220 total
Fat free yoghurt = 50 - 100 calories
Banana (depending on size) = 80 - 120 calories
Total = 500 cals (low estimate), 790 cals (high estimate)
Lunch:
Pasta salad (made with mayonnaise? Homemade? How many grams of pasta? Approximate portion?) = approx 400 - 600 cals (depending on mayonnaise content!)
Wholemeal roll = approx 100 calories
Low calorie crisps (I'm assuming rice cakes or something like snack a jacks) = approx 89 cals
Total: 589 (low estimate), 789 (high estimate)
Afternoon snack:
Apple = approx 40 calories
Nuts = these vary HUGELY, are we talking a handful of cashews or peanuts? Or more than a handful? You could accidentally be consuming 600+ calories in the nuts alone! 150 - 600 cals
Low fat yoghurt = 50 - 100 calories
Total: 240 cals (low estimate), 740 cals (high estimate)
Dinner:
Homemade spaghetti bolognaise = hard to estimate (do you use lean beef? How much oil? Do you add bacon etc) but giving the benefit of the doubt I'll estimate approx 600 cals
2 x slices garlic baguette = 60 cals per slice = 120 cals
Weight watchers mousse = assuming 50 cals
Fruit = anywhere from 30 - 100 cals depending on the fruit
Total: 800 (low estimate), 870 (high estimate)
Evening snack: 2 x biscuits (again, are we talking digestives, hobnob, chocolate?) = approx 90cals each = 180 cals
So running total assuming all your drinks are zero calorie (black coffee, water, diet fizzy pop etc):
Low estimate: 2309 cals
High estimate: 3369 cals
The second you factor in your drinks you can see how the calorie intake gets well out of hand:
Cup of tea with milk: 30 cals
Fancy coffee with milk: 100 cals
Full sugar fizzy pop: 120 cals
Gin and tonic: 150 cals
Glass of wine: 100 - 250 cals
Pint of beer: can be as much as 350 cals a pint!
My recommendation would be to aim to eat high satiety foods - porridge is great for example. Low fat anything (spread, yoghurts) are low satiety foods as the fat they take out of them they usually replace with sugar which will have you feeling hungrier quicker. As sad as it is to say, pasta is a low satiety food and won't be keeping you full for longer. Temporarily ditch it for lunch and pick higher fat foods like avocados, chicken and up your protein for more fulfilling meals.
Ditch the nuts as a snack, I find they are more calories than they're worth.
Drink water over anything else. If you have anything non zero calorie drink-wise absolutely count the calories, it's so easy to forget what you're consuming which leads to this sort of confusion when it feels like you're being good and seeing no progress.
And finally, up your activity level if you can, a 30 mins walk at lunchtime will help keep your energy levels up and stop you from staying sedentary most of the day.
I know it feels pretty hopeless when you've been working hard to try to lose weight and nothing seems to be happening, but it's so easy to accidentally lose sight of your consumption. Getting honest with the calories and what you're actually eating and drinking is the first step.
Good luck! Hope this helps.