Call Dr.’s Office or ER?

I’m 6 weeks pregnant with my first baby and I’m a little anxious. Today I had one spot of brown discharge in the morning, I know spotting is normal but it kind of worried me. I’ve also had occasional pulsing pains on my left side that happen less than once a day. I’ve also had similar pains on my right side and light cramping generally in my pelvis. I’m not sure if it’s anything to get worried about because it’s not constant and it’s not severe pain, but I don’t want to risk losing a tube if its an ectopic at the same time.