My 7 week old female puppy is having trouble weeing as she not going as much as she usually does and is like she's in pain she has no truble pooing could u advise me with what's wrong

Possibly a urinary tract infection.
Get a specimen jar from the drug store and collect a urine sample to take into the vet.
Having a sample ready before your appointment saves a lot of time at the vets.

I agree with Shaz here, UTI or balder infection could be a possible issue. Kidney failure or stones are less likely but still a possibility.

I agree with all the above. Go to the vet for more suggestions and I final answer.