What Causes Missing Periods And Nausea After Stopping Depo Shot?

Hi, I am 22 years old and I was on the depot shot for 5 years but I stopped it back in march. I have no had a full period since I stopped. Me and my husband have been trying for a child for the last 2 month. For about a month now I have been really tired, 2 days ago I felt sick to my stomach and my whole body hurt. I have never had a child before so I don't no but sometimes when I am just sitting around it kinda feels like something moving in my stomach an makes me feel a little nausea. Could I be pregnant?

Also I have another question for you. About a month ago I was laying down in my boyfriends bed and I started to feel tightness in the right side of my chest and was having trouble breathing. When I moved my right arm away from my chest it felt like it got tighter and made it harder to breathe. So the only way I could lay down and get comfortable was to cross my arms over my chest. A week after this I was driving out of state and my chest started tightening up making it harder to breath, then both of my hands went numb. I turned on the heat in the car thinking maybe that would help get the feelings back in my hands, but it didn't work. A few minutes later my right arm and my right leg went numb. Now I pulled over on the highway and had my mom drive the rest of the way. When we switched seats my whole face went numb and now I couldn't move. All I could do was cry because I was so scared and I had no idea what was going on. This was the second time I was having trouble breathing and the first time my limbs started going numb. What could this be? I have experienced the tightness of the right side of my chest more than the numbing. The numbing has been involved a few times but this don't happen all the time. In the last month this has happened probably 15 times but it really scares me. I shouldn't be having problems like this at 22 years old. Please help. Thank you