OP, I say get started with a good moisturiser for under your eyes, and also on your face. Try a few to see which you prefer. It should make a difference and make you feel better (there is nothing wrong with you btw!). Try Boots or Superdrug, look online to see which products have good reviews.
Make sure you wash your face with a good cleanser every morning and evening before you go to sleep. You could also try a sleeping moisturiser for overnight use if you have dry skin.
And, if you feel brave, you could try some glycolic acid and retinol. Do some research online, and speak to sales assistants on beauty stands in Boots, a department store etc for tips, as these need to be handled carefully.
For the long term, if you can, I'd try to cut out the processed carbs. When I don't consume these, my skin drastically improves (and so does my mental health and energy levels). Stick to lean meat, and veg and fruit (try to limit fizzy drinks, crisps, cakes etc). It's hard, but once you're over the hump, you should feel much better.
And exercising gives my face a real glow when I keep up activity levels. Highly recommend walking and strength based exercising at home.
Hope this helps 