All of the above advise is good and valid. Here's my two cents worth.
I expect bringing the charge up on that battery is going to solve most of your problems of the previous trip. More than likely, your battery was low to start with, for whatever reason.
I would check the volts before and during start and run to be sure it's okay. It should be at between 12.5 and 13v after setting a week on full charge. It shouldn't go below 9.75v during the start procedure or the battery has problems. And, it should indicate somewhere between 13.5 and 15v while running/charging. All this based on what I've read and experience.
Like several have said, it might be a bad connection, so cleaning and securing your battery connectins might be in order. Replacing the wing nuts with s/s lock nuts is also a good idea.
I don't know about others, but I check my batteries with a meter the day before using the boat, anytime it has sat for more than a few days. If either of the three is low, even a little bit, I put the charger on it. I want to know, I'm not going to have problems when I get out there, and I do fish at night quite a bit, so more the reason. Also, keeping a meter onboard for troubleshooting is a pretty cheap way to go. They are about 20 bucks at W/M.
Most will tell ya, if you are going to fish more than a couple of miles from land, it's a good idea to install a second battery for accessories and dedicate the current one to starting and the bilge pump, or one of the bilge pumps, if you have two. A second battery is cheap insurance against most electrical problems on the water.
Good luck with it.
Afterthought- Here's a site. which is probably an overkill of info on the subject, but might be of interest to some..The guy feels it is worth 10 bucks for the time he spent compiling it. Maybe so, I donno..
http://www.islandnet.com/~robb/marine.html
Whatever happened to free info on the internet???
Another subject for sure..
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