Need reassurance!!

Okay. I know everyone says not to get an u/s at 5 weeks because you usually can't see anything yet but my doctor wanted to due to a ton of cramping I've been having and I miscarried last time around this time. But when I got my u/s there was only a gestational sac no yolk sac or baby yet, which I mean I kinda expected. But I can't help but be worried due to a lot of other reasons... For example I've been having a TON of symptoms, extreme fatigue like basically needing to sleep every second I can, a ton of cramping, morning sickness seemed to start and I wasn't throwing up but was feeling extremely nauseous in the mornings.. And then yesterday I had almost no symptoms at all. I did have the morning sickness, but hardly any cramping and hardly tired. Is it normal for my usually constant symptoms to just not be there one day?? Or for a few days? My HCG levels were tested about a week and a half ago and were doubling. My last test said i was 1,300 ish. I'm SUCH a worry wart guys... I just need someone to tell me I'm either being totally crazy and I need to chill or I should be worried 😩