...am quite p****d:

{first: if you're a camera expert, please skip my blahblah, I have a question at the end. Thank you!}

Had to escape from this world's madness and managed to get the old bench for me alone to watch the sunset. A lovely one with a view over the hills, where the seven dwarfs dwell, until my fingers froze. And until I got p****d:

with my camera. Maybe also with other negligibilities too but at this very moment mainly with my camera!

You see a quite distinctive spot beneath the left black branch. With your eagle eyes I'm sure you spot also quite a couple of spot more. They are inside the camera (because they appear with every lense on) and I'm at the limit of my cleaning capabilities.
And, what you don't spot, recently nearly all pictures are quite over-exposured. With the same lenses in the same situations as always.
And, and at this point I had to take the rest of my photos with my phone camera, every bloody time I turn the camera on and focus it focusses and then the picture in the viewfinder turns greyish.

My question to you experts:
Obviously the camera (a Canon EOS 350D) has to cleaned professionally and probably repaired. It's now over 5 years old and I took quite 'a few' pictures.
Is the camera still worth the effort and the money of repairing and cleaning?
How many pictures is the camera supposed to take in it's lifetime?
I'd be very grateful for any suggestion or hint. Or any new camera.

Btw, I'm not in a too bad mood at the moment, my consolation in form of a leek mushroom pie with spiced hazelnuts and a spiced cranberry apple crumble is in the oven. I fear I've got carried away. Someone wants to come over to join?