For a first try it's alright, but some things are off:
- The reflections from the car are a bit wrong in ther perspective and I'd also blur them a bit more.
- If the car reflects on the ground, the sorroundings in the background should too.
- Too many raindrops in a too small area and they're also too dark.
- With so much rain, you would see water on the car and the ground, including sprinkles.
- The drops on the lense are a nice touch, but too clear and you can see right through them. Drops like these usually reflect the whole environment (mirrored, because they work like extra lenses):
Keep trying, I'm sure you'll have some great results soon!