Help!! I'm 20 weeks pregnant and I've had body aches since last Thursday night; I did some house cleaning and I figured…

Help!! I'm 20 weeks pregnant and I've had body aches since last Thursday night; I did some house cleaning and I figured it was normal because of that and just the fact that pains and aches are to be expected at this stage. Friday morning, my whole body was sore, especially my lower back, but since last night (Friday) I've had a severe headache that won't go away, I was reluctant to take any medication, but I've been having to take Tylenol to be able to handle it. Today, I've had the same symptoms, sore body; throbbing headache, I feel pressure behind my eyes; it feels as though I'm coming down with a cold or the flu but I don't have any other symptoms that would indicate so. I've also had a dull pain on the right side of my belly that goes from the top of my hip to the height of my belly button. Has anyone experienced anything like this? Should I call my doctor or head straight to the ER? Please help, I'm getting worried it could be something serious.