I have problems with anxiety and irregular heartbeat when i use decongestants containing phenylephrine, is there anything else i could take? i really need help.

Congestion: Your best bet may be a nasal steroid, a few varieties of which are available over-the-counter. As well, you can try an antihistamine, although some can be sedating. Two concerns, though: (1) with your sore throat, you may have an infection and (2) on phenylephrine your heart rate should increase but should not become irregular - has this been investigated?