Contractions @ 34 weeks

I started having contractions two nights ago but I went ahead and went to bed thinking it was nothing. Woke up feeling really weird and just not myself. My lower back was killing me and started having pretty intense contractions. Finally called my dr and he had me come in. They monitored me and the babies. I was having contractions every 5-6 minutes but they weren’t strong enough to change my cervix. Had my cervix checked and I’m still high, thick, and closed. Dr decided to do the swab test to see if I’m in preterm labor, and test came back negative. So they sent me home. I can continue to work and do everything as normal. Well today, I’ve had contractions all day still about 6-7 minutes apart. My back is killing me. I’m just at loss of what to do. Any other ladies experience anything like this? I’m expecting boy/girl twins.