I don’t know what is happening

So I did not have a period the whole month on December. On my other app my period was suppose to come the 27th but this app said the 24th because in November my period came on the 24 but I have trusted the other app because I just got this one and the other one had always been spot on so when the other app said I was 3 days late I tested and it was negative so closer to the end of the week I had period cramps and back aches but no period and I haven’t been stressed or gained weight or lost weight I don’t know what to think I have never missed my period I am just hoping I am pregnant but I just don’t know me and my husband has been trying but I have never been pregnant I know all of the pregnancy symptoms but like I have heard some women get them later on if they don’t get it now but like I don’t know what to think