Sick all the time 😭

I’m 18 weeks pregnant, and i just keep getting run down and then I get a cold. I feel one brewing right now and I’ve had 2 in the last 3 weeks. I’ve been eating healthy too! :( I love to exercise but this makes me feel worse when I do when I’ve got a headache and feel sick and out of energy. I feel bad for not exercising too because it’s so good for your body :(