I Had A Uti A Couple Weeks Ago And Got

i had a uti a couple weeks ago and got Bactrim to treat and symptoms didn't subside until the 6 day and after a week I got another uti with vaginal irritation which was from a spermicide condom I used both times before each uti which could of caused the uti in the first place. To treat my current uti I used Bactrim and have had symptoms for 8 days now so I feel the medicine isn't strong enough. the irritation has healed but my urethra is still red and feels irritated. what could it be and what should I do? I know to switch condoms which I will go back to the ones that don't cause anything when I can be sexually active after this.