Preterm contractions at 28 weeks

Went to L&D due to painful contractions. They ran urinalysis, cultures ( all negative)and tests to make sure I wasn’t in true labor. My contractions were between 2-4 min. My cervix was dilated to 1, effaced 40%. They did an internal sonogram to check the length of my cervix, my cervix was still thick. They gave me IV fluids, Tylenol and Benadryl.. they asked me if I wanted to stay in hospital until morning but I told them if nothing else is wrong with me I rather go home. Has anyone experienced this? Were you able to go full term or did you have your baby early? My biggest scare is that I may be having my baby too early if these contractions persist.