Is 35 too old for a baby?

Im nearly 35 and already have 2 children age 15 and 9, I've split from my husband 6 months ago as he went behind my back 2yrs ago and had a vasectomy knowing I maybe wanted another child and I couldn't move on from that. I am now seeing my childhood sweetheart who I've known 33yrs, he also has 2 children from a previous relationship, we are so in love and I know that he is my one. We were discussing last night me coming off birth control and trying for a baby, im supposed to take another depo shot on the 15th of this month. I would love another child but my only worry is my age, am I too old to be having another child? Are there any added complications? How long does it take to get pregnant after the depo?