should i get tested ?

So for the past week since maybe saturday, i been feeling like if i have have something down there. like a string or something. it could be itching. other thing is when i’m done peeing it burns and then i have to pee again but i just pee a little but it doesn’t hurt no more but the sensation is still there. and my lower back hurts. i have no type of discharge or foul smell. no bleeding. everything is normal except that. could it be something ? it goes and comes back.