I've Been Pretty Sick For The Past Few Days, I've

I've been pretty sick for the past few days, I've had an irregular heartbeat (it's been cautiously high) and about 3/4 the way through the day I noticed what seemed like my jugular hurting on the right side, but after feeling along the vein, it wasn't what was sore. Right below my jawline, almost right on the jugular there is a knot, where I can feel a relatively hard smaller vein I believe because I could feel my heartbeat it it.