Daily Tylenol use

From about 6 weeks till now ( I'm 21 weeks) I have had daily awful tension headaches. I have always had migraines but not daily. I have tried to not take meds but they get so horrible I feel flu like and throw up. I have been taking excedrin tension ( no aspirin) daily now with pretty good success. My ob said its ok and should be better in my second trimester but I feel awful like I'm poisoning my baby with meds  at such a vital time of growth and development. Does anyone else have experience taking Tylenol so often during pregnancy?