I just took ibuprofen about a half an hour ago, and want to take either dayquil or robittussin as well. is that overdosing?

No: Neither Dayquil nor Robitussin (guaifenesin) contain ibuprofen and it is safe to take the medicines in those formulas with ibuprofen. However, all of these treatments are purely symptomatic and will do nothing to speed your healing. Presuming you have a viral infection I recommend you also try Umcka (pelargonium sidoides), a herb proven to help people heal from colds, sinusitis and bronchitis more quickly.

Ibuprophen & dayquil: Ibuprophen is an NSAID-non steroidal anti-inflammatory( possible prostoglandin inhibitor) Nyquil contains acetominophen ( tylenol (acetaminophen) ) ,dextromethrophan a cough supressant and doxylamine -an antihistamine . Dayquil does not contain doxylamine-the antihistamine. The products are different classes of drugs and should not interact or result in overdose.