One final note to add from my point of view and this is a mistake I see happening in a lot of random groups. Make sure your group members are all DPS'ing the same target. Kill 1 NPC first, then move to the next. This will quickly take out 1 NPC at a time and significantly reduce the overall damage a group of enemies will do over the duration of the fight. Same for groups of enemies with a standard, strong and boss enemy. Kill the weakest targets first unless the stronger targets pose a serious threat. The weak ones will die fast and that takes a lot of enemy DPS out of the equation. Only the tank should occasionally hit the other targets to keep agro.

Stradoo, when I say "try pure CM or pure DPS" I obviously mean until the final tier skill. Once I have that, I will also spend my last few points points in the other 2 trees to get some good early skills out of them like the aim boost from tier 1 Gunnery for example. But I advise against putting for example 10 points in CM and 8 in Gunnery as a level 27 Commando because then you are just gimping yourself while leveling imho. It's better to focus on healing or DPS. Just try it for a few levels and see what you like best. The first respec is free. I don't know what the ones after that cost but I only assume it won't be overly expensive the first few times.

I wish to add to the previous 2 posts (which already contain very good info for you) that once you hit 27, you can have 3 skill points in the skill that gives you 100% chance (with 3 points in it) that when you use adv med probe, your next med probe will only cost 1 ammo instead of 3. Once you have that, healing becomes A LOT easier. Every time you use Supercharge, you just alternate adv med probe and med probe for 10 seconds and at the end of that 10 seconds, you still have 7-8 ammo left. It's amazing burst healing. Before 27, use the advice from the 2 posters above. Also keep in mind that it might not be your fault at all, maybe the tank in your group is too low level, undergeared or not using his defensive abilities. If someone dies, it's not always the healers fault. Lastly, at level 22, you get Concussive Round. It's a 1 minute crowd control with a 1 minute cooldown. Most classes get a similar CC ability in their early 20's. If the fight is too hard, remind your teammates that they could CC some enemies before diving in and going splat.

I'm a 29 pure combat medic and loving it. My DPS is still ok when I solo (with a DPS companion). I can handle Heroic 2+ quests solo with healing my DPS companion and I keep getting compliments from groups that I join that I'm doing a great job keeping them alive so that's always very nice to see and gives me that nice warm and fuzzy feeling that I'm doing something useful When BW put's in dualspeccing, I will definately set up a DPS spec as well, but for now, I'm very satisfied with being a combat medic. I would suggest, go pure Combat Medic OR DPS. try it for a few levels and flashpoints. Then respec to the other one, try that and see what gives you the most satisfaction. I would personally advice against hybrid specs, but it works for some people.

I must say, I'm a lvl 29 combat medic myself but I haven't gone to Tatooine yet so I don't know if there might be some really ****** bosses out there. But since you say it's only got 7K health, I can give you the following advice. If you are DPS specced, you could try using the healing companion (Elana Dorne) I haven't tested her yet so I don't know if she is any good at healing at all. But you can always give it a try. If you are healing specced then you should know why adv med probe is awesome and you should easily be able to keep one of your DPS companions alive (Aric for example) When I'm taking down elites / bosses solo, I send Aric on them (CC one of them if they are not alone) and I just heal Aric and occasionally DPS the NPC if Aric's health is ok. I've solo'd NPC's with 20k+ health on Nar Shaddaa so I don't see why you wouldn't be able to handle a 7K health NPC.

This may sound stupid but ... level to 24, get "Field Aid" from your trainer so you can dispell the life draining buff whenever the boss casts it on someone. Field Aid costs 2 ammo with a 4,5 sec cooldown and makes this fight a lot easier than before level 24.