Lower back and calf pain!?

13 weeks pregnant had this lower back pain for maybe a month, doesn't feel pregnancy related more like a pulled muscle or iv thrown my back out, sometimes it's fine other times it worse but I feel like an old lady walking or getting up sometimes. Anyways today iv been a lot more active than normal cleaning and I did carry a heavy load of laundry (I know I know but I needed to get it done there and then) now my lower back is really quite painful and I also have a sore ache in my left calf (left area of my lower back is what's hurting the most) the ache in my leg doesn't feel like a pulled muscle or anything I'm worried that it could be more serious like deep vein thrombosis or something... Only just feeling this ache in my leg. If it doesn't feel better tomorrow I will be going to urgent care just wanted to hear your thoughts!?