For coughs you can gargle with warm salt water and also drink hot chamomile tea with lemon and honey, drinking sprite can help too, depends on the type of cough/relieves sore throat
I just had the stomach flu, theraflu really helps! I know its hard to keep things down but you should try! Make sure to drink lots of fluid so you dont end up dehydrated, it requires forcing yourself! Try to get plenty of rest! Sinus colds are often caused by outdoor allergies, you can help prevent that by taking zyrtec and using a nasal spray, which are all safe after your first trimester
I know how you feel i had the same thing happen to me im19 weeks im still trying to get over my cough... i hope you feel better