One of the reasons why your body is rejecting the supplements you are taking is because they are not derived from a natural source. As a result, your body essentially treats it like a foreign substance, and thus it rejects it. I recommend you take the Women's Multi Gummies from mykind Organics (search the Garden of Life UK store online for this). The supplement I am advising you to take only contains organic and natural substances. The cost of the supplement is £24.75 for 30 servings, or 120 gummies. By taking 1 serving a day, which is 4 gummies, it will cost you £0.83 per day to take, rounded off to 2 decimal places. If it costs you £0.83 a day, it will cost you £5.81 per week to take. I consider that to be affordable, especially since the supplement is, in my view, the best in the market.
Now to cover the health aspect of the supplement. According to the product label, it gives you the total amount of Vitamin D you require in a day. With regards to your iron intake, try having 50g of chia seeds a day. According to Cronometer, 50g of chia seeds gives you 8.2mg of iron, which is enough for your daily recommended intake. I recommend you buy your chia seeds from Planet Organic. They cost £4.50 for a bag of 500g's worth, and so it will cost you £0.45 per 50g serving per day. Over a week, that is £3.15.The multivitamin supplement I recommended also gives you a lot of other vitamins and minerals. I believe I have given you a credible solution to your vitamin deficiency. The supplement comes in gummies, which taste nice as they have natural sources of sweetness. Be sure to read the product label to know exactly what is in it.
In general, I recommend you eliminate all sources of processed foods. We live in a society where it seems like convenience comes over health, which I find absurd. You can put a price on a packet of biscuits, but not on a human life. Try drinking only water too. I have only been drinking water since the age of 15 (I am 20 now), and that at 5l a day minimum. My urine is always clear, indicating that I am always hydrated. I recommend you try having 2l of water a day for a week. If your urine is consistently clear throughout the day, stick to 2l. If not, try increasing it to 3l a day for the next week. Keep on increasing the water intake until your urine is consistently clear. Also, make sure you factor in your activity level with how much water you need to drink. The more active you are, the more water you lose through sweat, and so you have to replace this water. I hope the advice I have given has helped. If you want any more help, be sure to message me...somewhere.