It's long but advice is appreciated

Alexa • I`m Alexa, hey everyone! I have a 3 year old and I really want another little baby. The fever is bad!
Okay, let me preface this with the fact that I do have two appointments, one with my OB and another with a nutritional specialist. 
Several weeks ago, almost a month now, I started getting these bouts of nausea, super tired, and unbearable indigestion and heart burn. They started right after I ended my last cycle. So for the last month it's been off and on. I've been reading and of course, webmd has me thinking I'm dying. I haven't been able to conceive since I had my miscarriage last July. I was reading on endometriosis and of course that's usually associated with really painful periods, which I don't have. How about blocked tubes? Has anyone had a miscarriage and not been able to conceive after? Note that with my daughter (healthy pregnancy), I was pregnant within two months. With my second pregnancy (that ended in miscarriage) it only took about 2-3 months. So now here we are months later and I'm having issues. Has anyone else experienced this? And now coupled with this whole crappy feeling I'm curious what's going on. 
Side note, I only have an appointment with a nutritionalist because I'm concerned it might be a developed food allergy. 
Also, if anyone has some good questions I can ask my doctor that would be much appreciated.