Why Does It Burn While Urinating And Itch At The Vagina After Sex ?

hi im 16 after i have sex with my boyfriend i always go 2 the bathroom and it burns when i pee it really burns then it itches a little at the opening. The first time i had sex this lasted for about 3 to 4 days. The second time we did it, it only lasted for 1 to 2 days. the first time he used a condum called huge. We talked about it and both agreed that the condum didnt feel right, so he used a different condum called magnum which felt a lil better but at least it didnt last longer and the pain wasnt that bad. Can you help me? What can you tell me to help me?