Prenatal pills make sick

hello so currently I’m 13 weeks pregnant these past weeks I can’t seem to take my prenatal pill! It makes me so nauseated to the point I throw up! My grandma suggested I take them before I go to bed but I wake up so nauseated and w a head ache I can’t even get out of bed. The dr gave me some nauseation meds but I tried it I didn’t like the effect it gave me. I haven’t been taking my prenatal like I should be :( will that harm the baby ? I take 1 at night time I wake up nauseated and don’t take another till the next night. :/