Permanent tooth feels loose?

One of my permanent front teeth feel loose. It hurts if I'm eating ice cream or something cold and it come in contact with that tooth. It only feels loose if I move it with my bottom teeth, I tried using my fingers and tongue, but it doesn't feel loose. I can bite into food no problem. I had 3 retainers and braces for about 10 years, but I haven't worn a retainer in about 3 years. If I try avoiding using that tooth while eating and try to stop playing with it, will it stop feeling loose? I have never been really good with brushing and flossing my teeth, but I have started brushing them twice daily for a few weeks now, but I'm afraid to floss my teeth, especially if they feel loose. I'm no longer covered under my mom's insurance plan, so I can't go to the dentist, cause I can't afford to pay for the appointment. So if there's something I cab do at home, that would be great.