Answering to the questions above, yes every pregnancy symptoms varies and wont be the same. In fact it will come and go. Not necessary you will have prolong symptoms of fatigue, nausea throughout pregnancy.
1) You dont need to seek medical attention as this is like the hormonal changes in the body for pregnancy mummies unless you have a very very bad dehydration, vomitting to anything like food, drinks, smell, etc.
2) Yes that symptoms come and go wont come back. My first pregnancy, no morning/night sickness except heartburn & acid reflux from 2nd tri till nearing birth. For second pregnancy, I feel fatigue through 1st tri and nausea but no vomitting. However it gets better now 2nd tri.
Need not worry much, as long as you eat healthily, properly, nutrious food items. Taking multivitamin prescribe and ask questions if you have doubt, with your gynae/doctor just to ensure you are all good since esp, that you mentioned youve miscarriage before this.