Can my husband deny me visitation with my son simply because I had to move to another state only 4 1/2 hours from them?

I left my husband in February of 2012 and moved into my fathers home which he then left me and my boyfriend in May 2012. My marriage had been done for a while, I tried many times to fix it but we had irreconcilable differences and just did not manage to get along and the love was no longer there. When I lost my job in August of 2012 bills became impossible to pay and this month I relocated to Des Moines, IA with my boyfriend, where I currently reside with him and his parents. I am a full-time college student online seeking out my Bachelors degree and currently unemployed, Austin(my boyfriend) has a good paying job already and works full time. While I was residing in Missouri, I did not see my son as often as I should have because my husband made it miserable always having to be on his terms, his way. My son stayed the night with me a total of 3 times between the months of May 2012 and March 2013; I had requested on multiple occasions that my son stay overnight but was continuously denied. Now that I am in Iowa, I have informed my husbands parents of my exact whereabouts, including address (he resides with his parents). I text numerous times a week asking about my son and his welfare, I request online video chats with him but am denied those as well or the family agrees to them but they never happen. Over the past week, I have chatted with my husband asking him for a 2 week visitation with my son here at my home in Iowa, again I was declined. From this point, I do not know where to go, how to go about things or even what I can do in general. Do I not have any rights to my son without a custody order? I feel as if my husband is isolating me out of my sons life completely. I have no criminal record, my current home is big enough for him to be in for visitations, I am not under any influences of drugs or alcohol and this is just making everything so much more difficult for me. I moved to Iowa because I was unable to find employment in Missouri.