Bleeding/Spotting

Trying to not stress, but its hard. On March 1st I found out I was pregnant. Everything was going fine and then starting on March 10th I began spotting. I haven't stopped since. It has been only when I wipe and its brownish/rust colored. I have had ultrasounds every week since then. On March 15th the the ultrasound measured me at 5 weeks 2 days vs 6 weeks 3 days that I thought I was based on my last period. My HCG had increased double and last week when I had an ultrasound the pregnancy sac had gotten better as well. This week I've felt like crap... exhausted, nauseous and nothing sounds good to eat at all. Yesterday I was bleeding when I wiped, but it was brownish red. No clots or tissue. Just there when i wiped and it was more than it had been during the week. Today I have another ultrasound cuz my doctor is monitoring me closely. I'm hoping to hear a heartbeat or fetal pole or something indicating the pregnancy is moving along. I'm just over this spotting/bleeding. Anyone have any issues like this...just trying to stay positive.