Is commuting BAD for pregnant women?

I was seated at the end of the bus the other day when we went to Pasay. Am 31 weeks pregnant and I felt like naalog tlga ako and I'm worried about my baby. I don't feel any pain sa tummy or balakang. I just felt tired since I was on that bus for 3 hours, but am still worried. The bus was full and I didn't know na pwede pla mag pa move sa pinaka harapan pag buntis, late ko na nalaman nung malapit na kmi sa destination namin. Dun palang kc na notice ng conductor that I was pregnant. He advised me to always sit at the front of the bus and that they always move pregnant women there and it's okay, you just have to tell them about your condition. He was very nice. Have you ever experienced ung ganun mga mommies? yung feeling nyo na naalog tlga kayo sa byahe? Do any of you commute from time to time? or Do any of you travel on a bumpy road? That was my longest commute because ever since I got pregnant iniwasan ko magbyahe ng magbyahe para iwas matagtag. no choice lang tlga kc me and hubby needed to take care of some documents.?