Baby fever

I ben having baby fever past few months, and my boyfriend already have a daughter in previous relationships and I want have children with him and he does too, but this would be my first child and I ben trying get pregnant past 9 months and my cycle is normal, I’m getting ready to start in 7 days what I can do after my period ends, there lube or anything that over counter, before I spend out 300 dollar for blood test, start feel like there something wrong with me.