My bitch is 50 days pregnant!
Slight white discharge on and off.
She already has lots of milk produced and sometimes leaking from her nipples.
Seems little uncomfortable!

Are these normal?

Please help me.

Heavily panting and having a slight fever on and off,
White odorless discharge is appearing on and off too.
Big belly and uncomfortable.
Milk being leaked from her tits.

Are these normal???

Have you called your vet? If not do it because they can go through with you as to whether you need to take your dog in.

It all sounds pretty normal to me.  Heavy panting is normal in late pregnancy.  How do you know she has a fever?  What is her temperature? 

White discharge is normal in the final stages of pregnancy.  A large belly is clearly normal.  Milk coming early happens sometimes, but please don't try to express it or fiddle with her nipples or you can induce labour prematurely.

Really the only thing you've mentioned which isn't normal is the slight fever, but if this is just going on appearance and what she feels like to your hand, it's not a fever....

Fever - I felt hot when I touched inside of her ears.
And she went off food
Started drinking lots of water
Lots of sweat out her mouth

My vet has gone abroad!
Went to a nother she prescribed a half a tablets of L-Trim antibiotic .

Feeling hot when you touch her ears is not a reliable way to measure her temperature.  You need to get an accurate thermometer and take her temperature up her anus, like vets do.  Until/unless you do that and find that it is higher than it should be, you cannot say she has a fever. 

Going off food in late pregnancy is very common.

Drinking lots of water if she is panting a lot, would be very common - she is losing water when she pants.

Thanks a lot!
She is more than a dog to me and my family. We have a bond between my dogs and my family members beyond from a typical bond from dog to owners or wise-versa. We are one family and it is incomplete without my dogs!

Thank you for your valuable experience, helped me a lot.
This is not just the first litter of hers, but for all of us.
I don’t want her to feel uncomfortable at any cost.

Thank you all!

Is there another vet you can go to even if its to take her temp.
Is the antibiotics safe for pregnancy?

I wouldn't give ABs for what you've described there - it sounds like perfectly normal developments for the end of pregnancy.

At 50 days, this is too early for a live litter to be born as the lungs are not yet fully developed. 

If it was my dog I would drive hundreds of miles to see a vet.  Being on holiday would not do for me, I would expect a vet to have cover.

There's nothing a vet can do if a litter comes prematurely, but there's nothing the OP has said to indicate her dog is in labour.  She is in a hot country, in the final stages of pregnancy...