I feel you, first trimester back pain is really rough especially when you're trying to work through it. Have you tried prenatal massage or a maternity support belt? They actually help a lot of mums I know get through the day without creams, though you might want to check with your PD first about what's safe for you specifically. Warm compress on the sore area, good posture at your desk, and taking short walks every hour or so also made a difference for friends of mine. The pain usually eases a bit once you're past the first trimester, so hang in there.
Maybe you can ask your husband to massage your back gently while you sit up or lay side. Don’t lay on your stomach.