Pregnant and dealing with a toddler

I'm in my third trimester and I have no patiences anymore. My three year old gets to me like no other. Is anyone pregnant and have a toddler? How do u get the patience for them? It's not that I can't handle him it's just my hormones are out of the roof and sometimes I just want to scream! Iv never had this problem till a couple weeks ago. I feel so bad cuz all I want to do is play with him and what not but sometimes I'm just like grrrrrr