Tested at what I thought was 10DPO and got a faint positive with a first response

Tested 3 hours later to receive a negative.  I have had sore boobs the past few days and my period was due yesterday.  I tested yesterday twice with a first response and received 2 faint positives.  Tested again this morning and received a negative.  Very confused and not wanting to waste money at the dr unless I need to...

 

Advice please?