What are the symptoms of being pregnant?

Ok for me symptoms started to show up about 1 to 2 weeks after with sore , and some cramping, lol its tricky it just felt like my period was coming, but it was weired because my were sore so much earlier. Honestly there is really no symptoms, i did,nt feel anything, when i first found out, maybe a week later of knowing i started to feel nausea and very weak, i didnt even go to the bathroom alot, so basically its kinda tricky you cant really tell if you are pregnant unless ur maybe after 7 weeks, this is when i started to feel all those crazy symptoms of nausea and headache and weakness. im am about 5 ft 6 and 128 lb and im 12 weeks pregnant and still no show of the bellly, hopefully when im about 4 to 5 months il be showing.