is it ok to take Tylenol extra strength while breast feeding?

I know this might sound like I'm being overly cautious but my oldest child was just diagnosed with ASD and ever since his diagnosis I've been very cautious about not taking excessive medication etc for fear it will pass in my breast milk. Today I have an excruciating tooth ache. I've been putting off pain meds for 8 hours and I don't think I can function anymore without. My dentist can't get me in until tomorrow. Is Tylenol ok to take while breast feeding? I keep feeling guilty for wanting to take it incase my daughter has some kind of adverse reaction from my milk after. Thoughts? TIA :)