Can I call my gyno about a urinary tract infection instead of seeing my gp?

Yes and more. The issue is about access, appropriate treatment, and follow-up. A urologist can also be consulted for a urinary tract infection. There has been instances in which patients have been on an antibiotic that is resistant to the bacteria identified on a urinary culture and sensitivity. Good followup prevents further complications.
Yes, but... Not all utis are the same. An isolated case, diagnosed recently will be usually treated with a 3 day course of abtx. Recurrent infections, or repeat symptoms inside of 6mos, or symptoms lasting long than 4-5 days may need more attention. Repeat or recurrent utis should be seen by doctor. A urine analysis and culture should be sent for repeat utis.
Yes!!! Absolutely! Gynecologists frequently deal with UTI in females and they should be able to give you the right advice and treatment.
Yes. Most gynecologists are very comfortable and willing to evaluate and treat urinary symptoms including potential infections.

Related Questions

When must a woman call her doctor if she thinks she has a urinary tract infection?

At that time. Because she needs to have her urine tested for infection and then started on antibiotics if she does in fact have a uti.

When must a man call his doctor about urinary tract infection symptoms?

At that time. So he can have his urine tested for infection and immediately be started on antibiotics, if needed.
Immediately. Due to male anatomy, there are very few situations that can cause a uti. This should be further investigated. Other causes could range from stones (kidney, bladder, urethra), prostatitis, fistulas, etc.