DH and I in a sexual funk

DH and I have been together for almost 6 years and we have a 4 year old and are struggling TTC #2. Anyone who has had k really TRY to conceive knows that sex can become mechanical and not spontaneous... But on top of that we are simply not connecting sexually. I feel like I've lost my ability to be sexy! I don't know how to flirt or come on to him! My biggest issue is how to initiate sex. I always just say something very unsexy like "wanna go lie down" 😳 which I know isn't good. We both just laugh at eachother out of discomfort when we are intimate. How do I fix this or get out of this lull! Help!!!!! Any suggestions are beyond appreciated!